David enlisted in the Union Army in 1862. He was enrolled August 10, 1862 in Company B of the 120th Regiment of the New York Volunteers and was discharged June 2, 1865. His description was given as follows: "Age 23 years; height 5 feet 6 inches; complexion, Dark; hair, Black; eyes, brown"

He was wounded at the Battle of the Wilderness - "… struck on the left side of the sturnam [sic] by a gun in the hands of a soldier from which injury he has never recovered. Also that at Fairfax Courthouse in 1862 he was taken sick with Typhoid Fever which has also helped to contribute to his physical disability."

"… he was treated in hospitals as follows: 1st in Reg. Hos. for Fever at Fairfax Courthouse from there sent to St. Allucious Hos. at Washington. Then to the Episcopal Hos. Philadelphia & remained nearly a year in 1862 & 1863. Thence to Chestnut (hard to read that word - may be "Chester" instead) Hill Philadelphia. Thence to Fort Schuylar. After being injured in the Wilderness 1st Reg. Hos. thence to Rhode Island, Portsmouth Grove & remained about a year in 1864 & 65."

Source - Declaration for Original Invalid Pension dated August 29, 1877

David Van Kleeck