Home   Genealogy   Forums   Search   Contact
MHO Home
MHO Home
 17th Century
 18th Century
 19th Century
 American Civil War
 World War I
 World War II
 20th - 21st Century

 Write for MHO
 Search MHO
 Civil War Genealogy Database
 Privacy Policy

WWI Sections
MHO Home
 WWI Home

WWI Articles
U.S. Army Model 1913 Cavalry Saber
Tragedy of the Somme
Second Battle of Ypres
Origins of WWI
Military Intel of WWI
Romania During WWI
British Infantry Tactics in WWI
Bullets Quickly Write New Tactics
Plague of the Spanish Lady
SMS Dresden's War
Air Recon in WWI
Angel of Mons
Who Killed the Red Baron?
308th Infantry during Argonne
Jutland, 1916
Endgame in Flanders, 1918
German Commerce Raiders
The Battle Tannenberg
The Great Retreat
Britain's Participation Justified?
Lafayette Escadrille Pilots
Dead Man's Penny
Financing War
One of Ten Thousand
The Design Was Not Passed On
Subverting the Sultan
The Russian Army in 1914
St. Etienne: The 36th Division
The Kerensky Offensive
Fighting for Respect

Birrion Sondahl Articles
The Battle Tannenberg
Battle of Lundy's Lane
Battle of Leuthen
Napoleon's Campaign of 1809

Recommended Reading

Tannenberg 1914

Tannenberg: Clash of Titans

The Battle of Tannenberg, 1914 
The Battle Tannenberg, 1914 
by Birrion Sondahl

The Battle of Tannenberg was the first major battle in World War I on the eastern front. It pitted the forces of Russia against those of Germany. The major battle was preceded by a much more minor affair at Gumbinnen which had a great influence upon the course of the campaign. The Gumbinnen encounter led into the actual Battle of Tannenberg where the German Eighth Army encircled the Russian Second Army. The result of the battle was near total annihilation of the Russian forces. There were many factors which played a part in the German victory. These included logistics, intelligence, terrain, and communication among others. Overall the Battle of Tannenberg was one of the only battles of maneuver conducted in a war which is remembered for its static positions. The German victory at Tannenberg allowed for the war to continue when an early Russian victory could perhaps have knocked Germany out of the war.

The start of World War I on the eastern front found Germany in a precarious position. The majority of her troops had been sent to the western front and committed to the offensive there as outlined by the Schlieffen plan. This left the eastern front ill prepared to defend against a Russian assault. The reason why Germany took such a risk was because the German high command had not expected the Russians to be capable of mobilizing in less than six weeks. The Russians gained an advantage in surprise by sending the first of their troops into East Prussia a mere eight days after the start of the war. The speed of this mobilization was primarily achieved due to the Russian's neglect of logistical preparations. [1] The result of this speedy mobilization was that Germany was threatened with a two front war with only a token force stationed on the eastern front.

The Russian forces which were being deployed upon the eastern front were under the command of Generals Samsonov and Rennenkampf. These two men have often been portrayed as bitter rivals [2] but this has been shown to be pure myth. [3] Each of these two Russian armies consisted of around 400,000 men. General Rennenkampf was in control of the Russian First Army and had been ordered to advance to the west and engage any German forces encountered. The Second Army under the control of General Samsonov was to “swing around south of the Masurian Lakes region into the rear of the engaged German force.” [4] The goal of these maneuvers was a double envelopment of the German forces on a strategic scale. The German army was to be caught between the Vistula, Masurian Lakes, and the Russian forces. The Russians hoped for a decisive victory which would clear the way to Berlin and an early end to the war.

Facing this Russian force, the Germans had a force numbering about 210,000 men. [5] These men formed the German Eighth Army and were under the command of General Prittwitz. This force had been deployed with the Vistula at its back. Upon learning of the early Russian mobilization, Prittwitz favored a retreat behind the Vistula but this plan of action was vetoed by the German High Command. As a retreat was out of the question, Prittwitz chose to follow a plan offered to him by his chief of staff, Colonel Max Hoffman. This plan called for the Eighth Army to concentrate a surprise attack against the Russian First Army in the vicinity of Gumbinnen. The expectation was that the Russians could be lured into an ambush upon the River Angerapp.

While it is true that the Russians had a significant numerical advantage, the Germans were much more experienced and well supplied. Colonel Lawrence G. Karch describes this material advantage in the following statement, “Each active German division contained 12 batteries of light artillery (twice as many as a Russian division), backed by 6 batteries of howitzers. Each active German corps had an attached battalion of heavy howitzers. Further, such impressive firepower was supported by an efficient logistics system fed by Germany's highly developed rail network.” [6] The Germans had also received much better prewar training than the Russians received. Karch describes the state of the Russian army in stark contrast to the Germans, “The entire [Russian] army was short a million modern rifles and a billion cartridges. There were not enough uniforms or boots. While Russia had 60 batteries of heavy artillery, Germany had 381.” [7] Due to their hasty mobilization, the Russians also lacked medical supplies and field bakeries. [8] This meant that the smaller German force was better prepared for a battle than the Russians.

In addition to these significant shortages, the Russian forces were also lacking in aerial reconnaissance forces. Although Russia had a large air arm, this force had been employed primarily on the Austrian front. In contrast to this, the Germans were able to deploy a significant force of reconnaissance airplanes on the eastern front. Armstrong describes the German airforce on the eastern front as consisting of the following, “Forty aircraft belonging to Feldflieger Abteilungen (field flying sections) 14, 15 and 17 and Festungs-Fleiger Abteilungen (fortress flying sections) 4, 5, 6 and 7 were at the Eighth Army's disposal.” [9] These aerial forces were to play a great part in discerning the intents of the Russian armies. They had already been used to determine that the Russians were approaching Gumbinnen.

The Battles of Stalluponen and Gumbinnen

In spite of the German's superior intelligence and logistics, the Gumbinnen operation did not go at all as had been originally planned by Colonel Hoffman. This was greatly due to the actions of the corps commander Major General Hermann von Francois. Acting without orders, Francois decided to take his corps into Stalluponen where one of the Russian divisions was resting. Stalluponen was a small town twenty five miles to the east of Gumbinnen. Although the attack upon it was successful in capturing 3,000 prisoners, it tipped off the Russians as to the German's plan to attack Gumbinnen. The bulk of the Russian losses were suffered by the 105th Regiment. After the attack, the remnants of the Russian force fell back from Stalluponen in disarray to the east. With the new knowledge that the Germans were in the Gumbinnen area in force, General Rennenkampf now chose to halt his forces and reconsider his advance.

Upon learning of Francois' attack, General Prittwitz immediately ordered him to withdraw to Gumbinnen. Francois replied insubordinately, “Report to General Prittwitz that General Francois will break off the engagement when he has defeated the Russians.” [10] The Stalluponen skirmish continued throughout the evening. Francois only broke off the engagement when his left became exposed to Russian fire. It was only then that he followed his orders to return to the Gumbinnen region.

The next day, August 19, the fighting was renewed. This time it was in the Gumbinnen area and marked the start of what is now known as the Battle of Gumbinnen. This battle began when a group of Russian cavalry came into contact with a regiment of German landswehr a short distance outside the town. Shortly after contact, the Russian cavalry dismounted and brought forward their artillery. With the addition of this extra firepower, they were able to drive the German force back. However in this effort, the Russians suffered around 400 casualties and expended the greater part of their ammunition supplies. [11]

Overnight, Francois' corps began a long march in order to contact the enemy. His force of the I Corps had now been supplemented by the 1st Calvary Division. Armstrong describes the march in the following manner, "The German 2nd Infantry Division moved through the Zulkiner Forest, while the cavalry rode toward Pillkallen. In so doing, they swung clear of the Russian flank and entered the gap left by the retiring Russian cavalry." [12] In the early hours of the morning, they came into contact with a Russian force made up of the 28th Division. As Karch describes, "Russian artillery initially put up a spirited defense, but when their ammunition ran low (an early Russian logistics casualty), the Germans prevailed." [13] The battle lasted well into the daylight hours. The Russian situation was only saved through a repositioning of the 29th Division which filled the gap left by the battered 28th Division. The German left flank now became a stale mate with neither side having an advantage.

The situation in the center was markedly different. Here the Germans had been forced to march all the way from the Angerapp and therefore they arrived much later in the day than Francois' corps had done. In the center, General von Mackensen's XVII Corps advanced against General Rennenkampf's III Corps. General von Mackensen was supported by two other corps. The Russians had been forewarned by Francois' earlier attack and were much better prepared for Rennenkampf and those forces supporting him. At first the German attack went well, but the Russian enclosed the flanks and two German corps were broken under heavy artillery fire. The Germans suffered additional casualties when "the German batteries of the 2nd Division mistakenly but effectively fired on their own infantry." [14] These forces retreated back to the west towards Konigsberg.

Rennenkampf chose not to pursue the defeated German forces. He did not even send reconnaissance forces to keep track of the rapid German retreat. The Russian cavalry could have kept up with the retreating Germans, but they were not deployed in this capacity. The main reason for this was because Rennenkampf still considered the German I Corps under Francois to be a threat. It had been checked but not defeated. The center and Russian left had been cleared, but Rennenkampf was always cautious as long as Francois remained in place on his right, he did not believe his position secure enough to risk a pursuit.

The situation was different at German headquarters. As Karch writes, "The uncharacteristic sight of defeated German soldiers streaming mob-like to the rear really unnerved Prittwitz." [15] Prittwitz now believed that the entire eastern front was lost and the only hope was a retreat to hold the line at the Vistula. This is what he had originally planned and the defeat at Gumbinnen only reinforced his belief that this was the only feasible plan. Prittwitz proceeded to phone Moltke and inform him of this. Moltke was horrified by this information and it did not take him long to decide that Prittwitz was not fit to command the Eighth Army. On August 22, Moltke appointed Major General Erich Ludendorff as chief of staff of the Eighth Army and General Paul von Beneckendorff und von Hindenburg as commander of the Eighth Army. It was in response to Moltke's telegraph asking him to come out of retirement that Hindenburg sent the famous reply, "Am Ready." [16] These two men were now moved to the eastern front as quickly as possible to assume their new responsibilities.

Meanwhile, the German intelligence forces had been doing their work. After the Battle of Gumbinnen concluded on August 20, a note had been found upon a dead Russian officer. This note contained the greater part of the Russian plans for the campaign. As Hindenburg recalled, "It told us that Rennenkampf's Army was to pass the Masurian Lakes on the north and advance against the Insterburg-Angerburg line. It was to attack the German forces presumed to be behind the Angerapp while the Narew Army was to cross the Lotzen-Ortelsburg line to take the Germans in flank." [17] In addition to the discovery of this note, the German intelligence forces had also been monitoring Russian radio communications. One of the first radio messages which was intercepted and decrypted was Rennenkampf's order to not pursue the defeated German forces. This was one of the last Russian radio transmissions which was sent in code. As Armstrong describes, "Less than a month's campaigning had indicated to the Russians that coded orders were often useless." [18] The reason for this was due to a lack of trained telegraph operators. The Russians now began transmitting their messages without encoding and the Germans benefitted from intercepting these messages.

Battle Preparations

On August 21, the day after the Battle of Gumbinnen, the Russian forces remained in their positions. In spite of repulsing the Germans the previous day, Rennenkampf believed that they would renew their assault upon the Russian positions. It is clear that at this point he did not truly understand that he had gained a victory over the German forces. The Russian cavalry spent the day searching for signs of the Germans. Finally that night, Rennenkampf decided that the Germans had indeed fallen back and he once again prepared to resume his cautious advance.

Prittwitz was now preparing for a full scale retreat to the Vistula while his replacement was still on the way. However, his mind was changed through the persuasive efforts of his chief of operations, Colonel Hoffman. Karch describes Colonel Hoffman as "arguably the best strategist during the entire war." [19] His actions in August on the eastern front would do much towards gaining this reputation. In order to convince Prittwitz to halt the retreat, Hoffman reminded his commander that any retreat to the Vistula would be threatened by the Russian Second Army under Samsonov. Any such retreat would leave the Eighth Army in an even more precarious position than the defeat at Gumbinnen had already left it. Hoffman believed that a more sound strategy would be to concentrate upon Samsonov who would not suspect an attack. As Karch describes, "Prittwitz accepted Hoffmann's advice, but then incredibly failed to inform Moltke of these changes of plans!" [20] Acting upon intelligence from the air reconnaissance forces and intercepted Russian radio messages, Prittwitz now began to move the Eighth Army to attack the Russian Second Army.

When Hindenburg and Ludendorff arrived on August 23, the Eight Army was still preparing for this attack. Colonel Hoffman had effectively taken over command from Prittwitz and was assigning tasks for the attack. Both Hindenburg and Ludendorff approved of Hoffman's plans and allowed the redeployment to go along as scheduled. This redeployment was a major process as Francois' I Corps, which had not suffered as greatly as the other forces at Gumbinnen, would be moved from the German left all the way to form a new right flank. This was done by rail and took a total of two days. Karch describes the rest of the dispositions, "The rightmost German corps at Gumbinnen redeployed by another set of trades to become the new German center at Tannenberg. Finally, the two German corps that broke and ran at Gumbinnen forced marched and reorganized en route to become the new Eighth Army left flank. Only a single German cavalry division was left to screen Rennenkampfs quiescent First Army." [21] The German center, the X Corps, was the weakest numerically. Hindenburg describes it as "thin, not weak." [22] The two wings were quite strong as the goal in the upcoming assault was to recreate Cannae on a strategic scale. The center was meant to bend but not break while the two wings would encircle Samsonov's army completely.

General Samsonov's army had been making slow progress since the start of the war. Armstrong describes their march as a "struggle" which only covered fifteen miles a day. [23] This slow rate of progress was quite unsatisfactory to General Zhilinsky, who continually encouraged Samsonov to pick up the pace. He finally detached the I Corps from the First Army and sent it to the south to join with the Second Army. His goal was to take pressure off the First Army by strengthening the Second. The German reconnaissance took note of this movement. After the Battle of Gumbinnen, General Rennenkampf now became the slower of the two Russian armies as he advanced towards Konigsberg. Between August 23 and 25, the First Army only advanced a total of twenty miles. [24]

August 25, 1914, was an important day for the German intelligence service. It was on this day that two radio messages were intercepted which helped to reinforce the German plans. Armstrong describes these two messages, "The first message indicated that Rennenkampf was not an immediate threat. Samsonov's message was somewhat garbled, but the Germans deduced from both messages that neither Russian army was aware of impending danger and that Samsonov and Rennenkampf were tending to diverge rather than converge their forces." [25] The first message had been the operational orders for the IV Corps while the second was orders for the XIII Corps. Having a nearly complete knowledge of where the enemy was would be of great help to the German forces. Once it became clear that Rennenkampf was marching very slowly upon Konigsberg and not converging with Samsonov, the Germans understood that they now had an opportunity to isolate and destroy Samsonov's army. As Hindenburg recalled, "In any case we must now have not the slightest hesitation in leaving but a thin screen against Rennenkampf's mighty force." [26] The attack would involve as many troops as the Germans could muster. This new intelligence made it clear that Rennenkampf would take at the very least four days to reach Samsonov.

Both Hindenburg and Ludendorff understood that it was of vital importance to begin the attack immediately. The entire Eighth Army was now ordered to attack the following day, August 26. This attack was completely unexpected by General Samsonov who believed "he was facing a single corps instead of a five-corps army poised to strike a mortal blow." [27] With this in mind, Samsonov was also preparing an attack of his own. His attack was directed in the vicinity of Soldau and to the north and northwest where he believed the German flank to be.

The Battle of Tannenberg

As August 26 dawned, the German Eight Army and the Russian Second Army were both advancing to attack each other. The difference between the two advances was that the Germans knew the location of the enemy while the Russians, relying upon their cavalry for reconnaissance, had only the vaguest of ideas as to the position of the Germans. The Eighth Army was now poised for a double envelopmentt. It only remained to be seen if they would be able to carry it out according to the plan.

The main German attack was to be carried out by the I Corps under Francois. And as had happened earlier in the campaign, Francois once again showed his ability for independent action and his defiance of his superiors. He had been ordered to attack and envelop Samsonov's left flank with assistance from the XX Corps. Their main opposition would be the Russian XIII and XV Corps. Francois' force was concentrated against Soldau and he was ordered by Ludendorff to begin his attack at dawn. Due to the slow march of his artillery support, Francois did not cooperate with orders and only attacked halfheartedly. As Armstrong describes, "after 3 p.m. he refused to send his troops farther ahead until all his guns had arrived." [28] The attack had only just started and it had already deviated from plan due to Francois' refusal to continue until his artillery arrived. Valuable time was being lost.

The German flanking maneuver upon the Russian left went much better than Francois' attack. Here General Mackensen's X Corps and General Below's I Reserve Corps were able to concentrate upon a single Russian corps with great success. General Mackensen concentrated his corps against the Russian 4th Division, which could not handle the weight of the German attack. The fighting lasted throughout the day, but the Germans had the advantage in each stage. The Russian artillery had faltered early leaving their infantry open to assault. Armstrong describes Mackensen's attacks as occuring in a "series of quick rushes." [29] From these attacks, it is clear that Mackensen understood the importance of speed in maneuver warfare. By the end of the day, his tactics had greatly contributed it to the rout of the Russian VI Corps. This force retired from the field to the south in the direction of Ortelsburg.

In the center, the Russians were on the offensive. It was here that the Germans were weakest, but the plan only required that they hold against the Russian assault. This was a difficult task as a significant number of Samsonov's forces had been concentrated for the assault. The Germans were slowly pushed back throughout the day, but they did not break. Thus at the end of the day the situation in the center was little changed. This was also true of Russian left flank where Francois had not pressed his attack. The Russian right was fast beginning to deteriorate. The retreat of the Russian VI Corps left the XV and XIII Corps both without protection upon their left flanks.

During the fighting on the 26th, the Germans had intercepted another important Russian radio message. This message was sent to Rennenkampf and informed the Germans that the Russian II Corps was being repositioned to the south to aid Samsonov. The Germans quickly sent orders to the 1st Cavalry Division to intercept the Russians and at all costs prevent them from coming to the rescue of Samsonov's army. In spite of the success of the day, Ludendorff was still quite concerned. This was due to the knowledge that the Rennenkampf was sending reinforcements. He believed that this force could turn the German flank and rather than the Russian Second Army being caught in a massive double envelopment it would be the German Eighth Army. The delay of Francois had been key for this left a great portion of Samsonov's force still intact. Dubeski states that "Ludendorff started to panic and lose his nerve, thinking of the size of the gamble." [30] This may have been stated too broadly, but it is clear that at this point Ludendorff had grave doubts about the possibility of success in the battle. Hindenburg mirrored these doubts, and would later describe his thoughts at the time, "How would the situation develop if these mighty movements and the enemy's superiority in numbers delayed the decision for days? Is it surprising that misgivings filled many a heart, that firm resolution began to yield to vacillation, and that doubts crept in where a clear vision had hitherto prevailed? Would it not be wiser to strengthen our line facing Rennenkampf again and be content with half-measures against Samsonof? Was it not better to abandon the idea of destroying the Narew Army in order to ensure ourselves against destruction?" [31] The commanders of the Eighth Army were in doubt as to what would be the next best step in their campaign.

It was now that Colonel Hoffman once more stepped to the forefront of events. Dubeski describes Hoffman's actions, "He said that he knew a secret that would turn the battle in their favor. He told them an anecdote from his experiences as an observer in the Russian-Japanese War of 1904-1905. Hoffmann said he knew that the Germans could concentrate their forces against one Russian army and then the other because the Russian generals hated each other and would not come to each other's aid." [32] This was a completely false anecdote, yet it served to encourage Hindenburg and Ludendorff. It was indeed enough that, as Hindenburg recalls, "We overcame the inward crisis, adhered to our original intention, and turned in full strength to effect its realization by attack. So the order was issued for our right wing to advance straight on Neidenburg, and the left enveloping wing 'to take up its position at 4. a.m. and intervene with the greatest energy.'" [33] The crisis of the battle had been overcome greatly through the efforts of Colonel Hoffman and the battle would continue the following day according to plan.

The fighting renewed at daylight on August 27. Francois' artillery had now arrived was in position to support a renewed advance. As Armstrong describes, "At dawn, 28 field and eight heavy batteries crushed the opposition near Usdau, and then the I Corps infantry overran the Russian positions." [34] In many ways these tactics were similar to those carried out by Mackensen the previous day. The greater part of the Russian right had now been defeated and fell back towards Soldau. However, one brigade did launch a successful counter attack at Heinrichsdorf which did much to check Francois' pursuit. Despite this check, Francois continued with a pursuit to the south and southeast. His original plan had been to proceed to Neidenburg but this changed due to an intercepted Russian radio message. This message referred to the possibility of Russian reinforcement by the 3rd Guards Division from Warsaw. [35] Francois did not wish to engage fresh Russian troops and therefore limited his pursuit.

Meanwhile, the Russians were attempting their own envelopment maneuver against the German XX Corps and 3rd Reserve Corps. The main part of this attack was carried out by the Russian XV Corps. This assault was launched at daylight on August 27th. As the XX Corps was fresh, it was able to handle itself throughout the day without breaking. Once again, the Germans benefited from being warned in advance of the Russian movements by radio intercepts. With knowledge of the intent of the Russians, the Germans were able to counter their moves and make sure that the line held strong. However, in spite of this knowledge, the German center was still very hard pressed by the Russian assault . General Samsonov was dedicated to achieving a breakthrough and had concentrated as many troops as he could against the German center. As Dubeski writes, "The German centre suffered considerable disarray in the severe fighting." [36] Several battalions broke and fled, but as a whole the center once more simply gave ground rather than breaking. This continual push forward placed Samsonov's troops deeper into the trap in accordance with the German plan.

Throughout the day, much more reassuring news had reached Hindenburg and Ludendorff. The night before they had been reinforced by Hoffman's tale, but now they had concrete intelligence material. As Hindenburg recalls, "Moreover, we learned that it was only in the imagination of an airman that Rennenkampf was marching in our rear. The cold truth was that he was slowly pressing on to Konigsberg. Did he, or would he, not see that Samsonof's right flank was already threatened with utter ruin and that the danger to his left wing also was increasing from hour to hour?" [37] Once again the Germans could act in confidence without expecting the entire of Rennenkampf's force to fall upon their flank and rear. The situation had become much clearer throughout the fighting on August 27th and the two German commanders now agreed that the encirclement of the entire Russian Second Army was within reach. That evening they dictated the orders which would complete this encirclement.

The fighting continued on August 28. General Samsonov had now moved to the front and taken personal charge of the XV Corps. Once again, his orders were intercepted by the Germans. Armstrong describes the contents of these intercepted messages in the following statement, "more intercepted radiograms from the Russian XIII Corps disclosed that it was marching from Allenstein southward to Hohenstein and that its vanguard would arrive in Grislienen, five kilometers north of Hohenstein, at noon." [38] As a result of this knowledge, the German I Reserve Corps was directed upon Stabigotten-Grislienen. This would place them in the rear of the Russian XIII Corps. This would prevent the Russian XV Corps from receiving any reinforcements. The German I Reserve Corps engaged the Russian XIII Corps at Grislienen where a battle raged throughout the day with neither side breaking. General Samsonov remained with the Russian XV Corps, which was now heavily pressured in the vicinity of Waplitz. The fate of the Russians was now becoming clear to Samsonov, who seemed to place his only hope in fighting his way out with the Russian XV Corps. As Armstrong relates, "when Samsonov arrived [at Waplitz], [he] embraced the XV Corps commander and told him, in a melancholy tone of voice that inspired little confidence, 'You alone will save us.'" [39] Both Russian flanks were now in full scale retreat and were being rolled up by the German forces. Only the center could truly be considered to remain intact as night fell.

The morning of August 29th found the Germans in an excellent position. As Hindenburg recalls, "The ring round thousands and thousands of Russians began to close. Even in this desperate situation there was plenty of Russian heroism in the cause of the Tsar, heroism which saved the honour of arms but could no longer save the battle." [40] Karch also gives a description of this day's events, "Francois opened up with another great artillery barrage that shattered the remainder of the Russian left flank. This permitted his corps to block the route of retreat of the entire second Army. In the center, two Russian corps continued to fight well, but their situation deteriorated rapidly caught in the crushing jaws of an enormous double envelopment."[41] The Russian forces under Samsonov were all but completely encircled by the Eighth Army. Those which had not yet been defeated openly in battle were concentrated in the Neidenburg-Willenberg-Passenheim area. Throughout the day, defeated Russians had been surrendering in large numbers. Hindenburg himself had received the surrender of two Russian corps commanders at Osterode. [42] By the end of the day, the prisoners numbered in the thousands. The Prussian center had bent but not broken and now time was running out for Samsonov. If he did not manage to fight his way out with the XV Corps soon, he too would be forced to surrender.

Meanwhile, to the north, Rennenkampf remained oblivious to his comrade's predicament. His orders of the night of the 29th and the morning of the 30th have been described by Armstrong as follows, "one such message indicated that during the Russian II Corps' countermarch, which had been ordered for the second time, the soldiers were to demolish all railroads and telegraph wires west of the Konigsberg-Rastenburg line, including those at Korschen and Tastenburg." [43] Others of his orders mentioned that he was planning a great encirclement of Konigsberg, where he believed the primary German force to be located. Once again, Russian reconnaissance and intelligence forces had proved inadequate. When the Germans intercepted these messages, it was quite clear that Rennenkampf would not be arriving on their flank. Hindenburg and Ludendorff were once again reassured that their flanks remained secure and returned to concentrating upon the task at hand – the annihilation of Samsonov's army.

There was one more hope for the remnants of Samsonov's force. This came from the reinforcements which were marching from Myszaniec. As Hindenburg described, "On August 30th the enemy concentrated fresh troops in the south and east and attempted to break our encircling ring from without." [44] As the Germans were now formed roughly in a ring around the Russian center, these reinforcements arrived in the German rear. Hindenburg and Ludendorff did not have many forces which were not already engaged in the destruction of the remaining Russian forces within their encirclement. Therefore they were only able to send the weak reserves of Francois and Mackensen's corps to counter the Russian reinforcements. However, these Russian forces had become strung out across twenty-three miles in their advance and therefore "the attempt to mitigate the catastrophe to Samsonof came to naught." [45] When this relief attempt was repulsed, there was no hope left to Samsonov's forces.

Scattered Russian forces continued to resist throughout August 31st. It was only, as Armstrong describes, on the evening of August 31st that, "Zhilinsky finally judged the battle to be lost." [46] He now ordered those Russian troops which were not surrounded to retreat to the east. This included Rennenkampf, who during the entire period of the battle had achieved absolutely nothing. His cavalry had made a tentative approach to the German positions, but naught had come of this. The battle was now over. Armstrong describes the outcome, "the Russian Second Army had lost an estimated 30,000 troops killed, and the Germans claimed to have taken a total of 92,000 prisoners and 300 guns." [47] Keegan and Strachan gives the same number of prisoners, but place the casualties higher at 50,000 killed and wounded. [48] German casualty estimates vary, Blair gives them as 10-15,000 men. [49] Michael Duffy gives the total as "fewer than 20,000 casualties" and claims that "in addition to prisoners captured over 500 guns." [50] He also notes that it required sixty transport trains to bring the bounty of the victory back to Germany. The German victory over Samsonov's army was complete. Two entire corps had been destroyed and the rest had been severely beaten. Of the total of 150,000 men who were encircled, perhaps only 10,000 reached safety.

This great victory gained its name from Ludendorff. As Armstrong writes, "Ludendorff chose to name after the nearby town of Tannenberg, 'in memory of that other battle long ago [in 1410] in which the Teutonic Knights succumbed to the united Lithuanian and Polish hosts.'" [51] The battle now went into history as the Battle of Tannenberg. The events of the battle were quite straight forward. The reason for the victory is more difficult to determine.

Reasons for Victory

There are a number of factors which contributed to the German victory at Tannenberg. One of these primary factors was the lack of Russian logistical support. As Karch writes, "Soon after hostilities started, many Russian artillery batteries were limited to firing no more than four rounds per day due, in part, to a lack of transport for munitions." [52] This lack of ammunition resulted in a lack of sustained firepower capability. In this age before tanks, artillery was very important to successful operations. As Colonel S.L.A. Marshall noted about the second world war, "And yet, until the day of final surrender, the far purpose of all movement in war is the upbuilding of one's own fire power [italics added] and position at the expense of the enemy's power and position." [53] He continues, "The familiar words of Napoleon: 'It is on supply that war is made,' simply underscores the fact that primarily war is made with fire, and that logistics have a decisive effect upon the arena only when they enable military forces to bring a superior fire to bear." [54] The first of these statements shows how important fire power is to victory in battle. The second shows how important logistics is to upholding fire power. Throughout the battle of Tannenberg the Russians were lacking in both logistical support and fire power capability. They had the artillery available, as can seen in the number of guns captured by the Germans, but they did not have the munitions to be able to put this artillery to good use. It should also be noted that the Russians were lacking in ammunition for their rifles as well. Turning once again to Karch, "The entire army was short a million modern rifles and a billion cartridges." [55] He refers to the entire Russian army, not simply those involved in Tannenberg, but nevertheless it is clear that there were many supply shortcomings in the Russian armys at Tannenberg. The Germans did not suffer from similar shortfalls. Their only lack of firepower came due to the slowness of transporting their artillery. This was almost critical on August 26th, when Francois refused to press the attack until his artillery had arrived. As Armstrong describes, "The main strike would be launched in the area of Soldau by I Corps, but its commander, Francois, balked at Ludendorff's orders to attack at dawn on the 26th. One-quarter of his field guns, his heavy guns and his artillery supply columns had not yet arrived, and his losses at Gumbinnen had taught him the folly of attacking with inadequate artillery support." [56] At Gumbinnen, the Germans had indeed been defeated due to lack of artillery. At Tannenberg, it was the Russians who lacked substantial artillery support. Once Francois' artillery did arrive, his corps was able to tear apart the Russians facing him. As Blair notes, "modern historians such as John Macdonald recognize the great importance that logistics played in the Russian battlefield disaster, noting that 'Russia certainly had an abundance of manpower, but was woefully lacking in administrative ability; nor was there competent machinery to keep thousands of soldiers supplied in the field.'" [57] It is clear that supply troubles had contributed greatly to the Russian defeat.

The Russians were also severely lacking in reconnaissance forces. This was due to their sole reliance upon cavalry for reconnaissance. This cavalry was composed mostly of Cossacks. Armstrong describes their actions on August 21st, "The large Cossack cavalry units on which the Russian armies relied for intelligence were so uncontrollable and inefficient that it was not until that evening that cautiously advancing Russian infantry discovered that the Germans had retired and were miles away." [58] If the Russians had a more reliable reconnaissance force, they could easily have discovered the retreat of the Germans from Gumbinnen in time to carry out a much more efficient pursuit. Instead they wasted the day awaiting another German attack and allowed the German forces to escape unmolested. It has been noted that the Russian army was too disorganized at this point to continue a pursuit, but nevertheless the day could have been spent much more productively than simply awaiting a phantom attack. In contrast to the Russian cavalry, the Germans had a much more efficient reconnaissance force in their airplanes. As Karch describes, "In what must have been the first large-scale use of tactical airborne reconnaissance, the Eighth Army employed observation aircraft to locate Russian forces. On the other side, the Russians sent all their aircraft to the Austrian Front for some unexplained reason. Had the Russians just one aircraft to spy on the Eighth Army, Tannenberg may never have happened. Of course, if Rennenkampf had used his many cavalry divisions to keep an eye on Eighth Army movements, Tannenberg may still have been avoided." [59] It is true that the aerial reconnaissance of the Germans could make mistakes such as when an airman reported that Rennenkampf was beginning to march south towards the German left flank and rear. [60] But overall, the air arm proved exceptional in its ability at determining the location of the Russian forces.

In addition to reconnaissance, intelligence played a huge part in the German victory at Tannenberg. One of the great questions of the battle is why the Russians were so naive as to transmit their complete orders in the open. There are a number of excuses for this lack of regard for radio intelligence. One was their lack of training. Their operators were not sufficiently trained in encoding and decoding methods to make encrypted messages efficient enough for use. Even when they did use encoded messages, these were easily broken by the German forces. Another reason was a lack of telegraph wire. As Armstrong describes, "Corps headquarters had only enough wire to connect with the divisional commanders, not enough to connect with army headquarters which continually lagged too far behind-or with neighboring corps. Consequently, radio became the preferred means of communication for the Russian armies." [61] This once again points to a lack of sufficient logistical support. The hasty mobilization had resulted in a lack of many support services and materials which were of vital importance to the war effort. Armstrong pays especial detail to matters of intelligence in his account of the battle. As he describes, "In actuality, Ludendorff came to depend on several dozen intercepts that his staff regularly collected during the day, then decoded or translated and sent to him every night at 11 p.m. If they were late, he would become worried and appear personally in the signal corps room to find out what was the matter. Colonel Hoffmann was more forthright in acknowledging the value of the intercepts. 'We had an ally,' he wrote, 'the enemy. We knew all the enemy's plans.'" [62] Karch supports this conclusion, "Along with tactical airborne reconnaissance, the Germans also made outstanding use of intercepted Russian radio messages, which were conveniently broadcast in the clear or in easily broken codes. Ludendorff personally received these intercepts and issued orders accordingly with little delay." [63] These radio intercepts did much to reassure Hindenburg and Ludendorff during the critical moments of the battle. It was due to radio intercepts as well as their airborne reconnaissance that they were able to determine that Rennenkampf was not marching on their rear. Their reconnaissance had at first been mistaken on this but they were able to clarify it through the intercepts and further reconnaissance. These two arms worked together well and did much to contribute to the German victory at Tannenberg.

Another contributing factor to the Germany victory was the terrain. The Germans were fighting in their own territory and had knowledge of the lay of the land. As Hew Strachan explains, "East Prussia was where the German general staff had learnt its craft in staff rides and manoeuvres. It knew the ground, and Schlieffen had taught that in a defensive battle the Masurian lakes provided the opportunity for operations on interior lines." [64] The Germans took advantage of this knowledge and their experience with maneuvers in the area. The Russians did not have a similar knowledge of the terrain. This had an especially negative affect upon General Samsonov. First of all, the terrain influenced the communications of the Russian forces greatly. The lack of telegraph wire has already been noted and radio contact was not entirely reliable due to the lay of the land. In fact, throughout much of the battle Samsonov had little or no contact at all with his flanks. As Gurko writes, "The absence of news was due to the difficulty of maintaining connection in such open fighting and also to the fact that both the flanking corps were moving, and had the utmost difficulty in maintaining any kind of communication with the other commanders." [65] The terrain in which the greater part of the battle occurred has been described as a "bewildering and fatal maze of marshes, creeks, lakes, and quagmires." [66] The entire battlefield covered around 200 square miles. [67] In this terrain, the Russians often became lost. Once again following Gurko's account, "Destitute of any information concerning the other troops under his control, Samsonof lost all power of directing operations and thus infringed one of the elementary rules of military strategy, that which provides that the commander of an army shall choose as his headquarters some spot where information can readily be brought to him and whence he can communicate with all the forces under his command." [68] General Samsonov had placed himself with the troops in the center of the Russian line. Here the battle went well for several days, as it was opposing weak German forces. In fact, it went so well that "General Samsonof's immediate observation was such an encouraging picture that final victory appeared a matter of certainty." [69] It was not until the night of August 29th that it became clear to Samsonov that all was lost. As Armstrong describes, "Horrified by what he saw as his disintegrating army retreated through the woods on the night of the 29th, he spoke of ending his life. His staff tried to dissuade him, but during one of their rest halts they noticed that he was no longer among them; then a shot was heard." [70] Samsonov had taken his own life, but it was the terrain which had contributed significantly to the loss of so many other Russian lives. As Blair notes, "Attempting to escape, the Russians 'broke and took to the fields, only to find that what appeared to be solid ground was in fact an impassible bog in which horses, men, and guns slowly sank from sight.'" [71] Due to a better knowledge of the area and communications abilities, the Germans did not suffer a similar disorientation and were able to move efficiently throughout the area.

Another item of note about the German victory at Tannenberg was the totality of the German effort. Everything had been thrown against Samsonov. The entire Eighth Army had been concentrated in order to gain a local superiority over Samsonov's army. Hindenburg recalls how "Everything must be thrown in which could prove of the slightest use in manoeuvre warfare and could at all be spared." [72] The garrisons from the fortresses of Graudenz and Thorn and the trenches covering the Masurian Lakes were nearly emptied in the effort to gain this superiority. The only troops not committed to the battle were those left to cover Rennenkampf. These consisted of simply a "cavalry division and the Konigsberg garrison with two Landswehr brigades." [73] Had Rennenkampf not been so cautious or had better intelligence as to the German location, he could easily have marched through this opposition and fallen upon the German left flank en masse. But he chose to slowly advance upon Konigsberg and the Germans were therefore capable of surrounding Samsonov with the entirety of their force and achieving the victory of Tannenberg.

Another great question which has been raised about the battle is why Rennenkampf did not march to relieve Samsonov. A great part of this has been explained in the failure of his reconnaissance forces. Another explanation has been given by Karch, "Samsonov and Rennenkampf were old and bitter rivals going back to the Russo-Japanese War." [74] This explanation however comes from Hoffman's anecdote which has become a part of what Dubeski calls the "victory myth" of Tannenberg. He explains, "It looked like Hoffmann's anecdote 'saved the day' for the Germans, yet it contained no literal truth. Russian historians documented that on no occasion did General Rennenkampf and General Samsonov ever get into a violent dispute or even have the opportunity to do so." [75] Therefore it must be concluded that Hoffman's anecdote was simply made up on the spot in order to boost the morale of his commanders who at that time were beginning to weaken in their resolve to carry out their ambitious plan of double envelopment. So the question remains as to why Rennenkampf did not move south with his whole army. The only plausible explanation must be that he, like Samsonov, did not realize the gravity of the situation until it was much too late. This must be explained by the paucity of the Russian communications. As it is known that Samsonov lacked communication with even his own flanks, it is quite reasonable to believe that any true communication between the two armies was next to impossible. Coordination between the two armies was being attempted through the efforts of General Zhilinsky. As Armstrong describes, "Zhilinsky, whose orders to his army commanders had become increasingly reactive and belated, unjustly accused Rennenkampf of failing to control his army. He was genuinely surprised when Grand Duke Nicholas reported to the czar, 'I am inclined to think that General Zhilinsky has lost his head and in general is not capable of controlling operations.' Zhilinsky, not Rennenkampf, ended up being relieved of his command." [76] It seems that the major reason why Rennenkampf never relieved Samsonov must be attributed to the communications breakdown in the Second Army and between headquarters and the armies. Zhilinsky was too far back to adequately grasp the situation while Samsonov was too far separated from his forces to do the same. Therefore by the time the situation became clear to either of these men, it was far too late for Rennenkampf to come to the rescue.

There is no doubt that the Battle of Tannenberg was a significant victory for the Germans. If the Eighth Army had been lost, the way to Berlin would have been wide open to the Russian armies. Instead the Russians were driven out of German territory and as Duffy writes, "no Russian army penetrated German territory again until the close of the Second World War, in 1945." [77] Hindenburg and Ludendorff have been given credit for the victory as the commanders, but Colonel Hoffman deserves much of the credit. He had created the plan and convinced Prittwitz to put it into action prior to the arrival of the new commanders. And then when Hindenburg and Ludendorff began to vacilate, he came up with the anecdote about the rivalry between Samsonov and Rennenkampf which kept them dedicated to the plan. The German intelligence and reconnaissance forces also deserve credit for the victory. The Russians can be blamed for their failure to adequately support their forces with a logistical backline as well as they inability to maintain communication and failure in reconnaissance. As is always true in war, there were many reasons why the Battle of Tannenberg ended as it did. A study of the battle helps to give insight to the numerous complexities of war which have persisted across the ages.

* * *

Show Footnotes and Sources

* * *

Copyright © 2008 Birrion Sondahl.

Written by Birrion Sondahl. If you have questions or comments on this article, please contact Birrion Sondahl at:

About the author:
Birrion Sondahl recently completed his degree in Military History from American Military University. In addition to studying military history, he is an avid freestyle skier. He lives at home with his parents, three cats, and a flock of chickens in Spirit Lake, Idaho.

Published online: 06/01/2008.

* Views expressed by contributors are their own and do not necessarily represent those of MHO.
© 2018, LLC Contact Brian Williams at: