Marshall was born about 1844.
Private in Company A of the 54th Massachusetts Volunteer Infantry of the Union Army, the first regiment in the United States made up entirely of enlisted men of color. He was about 19 years old, single and working as a laborer when he enlisted on 7 May 1863 in Newbury [sic], South Carolina. He was missing in action on 18 July 1863 at the Second Battle of Fort Wagner, and we must presume he was killed in action.
There is a Marshall Lamb who served in the 1st USCT and survived the war.
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