Thomas Mifflin of Pennsylvania served with John Trumbull as an aide-de-camp to General George Washington in the Revolutionary War. Trumbull painted his portrait, along with four other miniatures in this set, between 1790 and 1792 while traveling up and down the eastern seaboard during an intense period of portrait-gathering. Trumbull probably used this miniature for his two depictions of Mifflin. In The Death of General Mercer at the Battle of Princeton (1832.6.1), he appears mounted on a white horse at the far left, and in The Resignation of General Washington (1832.8), Mifflin, who was president of Congress at the time, is shown seated at the far left. One of the leading men in colonial Pennsylvania, Mifflin later became governor of the state and a member of the legislature.