Quarter-Master Sergeant William Marshall was born in the Parish of Barony, Glasgow and enlisted in the 95th Regiment from the Lanarkshire Militia at Dunbar in May 1811, aged 18 years. Posted to the 3rd Battalion, he was embarked for the Peninsula at the end of the year and in addition to the Battles of Vittoria, Nivelle, Nive, Orthes and Toulouse, he fought in a number of smaller skirmishes prior to returning home as newly promoted Sergeant in July 1814. Two months later he sailed for America and was more than likely present with the Left Wing of the Battalion at the Battle of New Orleans and afterwards at the surrender of Fort Bowyer. Once more returning to the U.K. in early June 1815, Marshall was hospitalized at Dover while his comrades rushed to join Wellington's Army at Waterloo.

Rejoining them at a later date for a short stint of service in the Army of Occupation in Paris, he was next posted to Ireland, where he remained employed on garrison duty until late 1825, a period that witnessed his advancement to Colour-Sergeant in July 1816 and to Quarter-Master Sergeant in July 1824, in addition to his transferral to the 2nd Battalion. With the latter he sailed for Malta in early 1826, where he was to remain stationed for six years, in addition to a final overseas posting to the Ionian Islands. Marshall was discharged in July 1834 and signed the receipt for his Army L.S. and G.C. Medal in December of the same year. He died at Chatham, Kent in June 1853.