7th Delaware Infantry

7th Regiment - Organized at Wilmington, Del., for 30 days July 12, 1864. Guard duty on Philadelphia, Wilmington & Baltimore R. R. at Havre de Grace, Oconowingo Bridge, until July. Moved to Baltimore, Md., July 16, and duty in the defenses of that city until August 12. Attached to 3rd Separate Brigade, 8th Army Corps, Middle Dept. Mustered out August 12, 1864. Regiment lost 3 by disease during service.

According to Delaware Civil War records, William’s muster-In document from July 12, 1864 shows he was now in the 7th Regiment, and was the 1st First Sgt for Company G under his brother Capt. Robert J. Holt.