In the early summer of 1776, Delaware's delegate to the Second Continental Congress, Thomas McKean, became the primary instrument in breaking that body's stalemate on the crucial question of whether the American colonies should remain within the British Empire. Several months later, he was signing his name to the Declaration of Independence. A vocal critic of English rule ever since the mid-1760s, McKean served in the Congress throughout the Revolution. His lofty and often tactless manner, however, antagonized many, and as chief justice of Pennsylvania after the war and later as governor of that state, McKean was frequently the center of controversy.

Artist Charles Willson Peale painted likenesses of McKean on numerous occasions between 1776 and 1800. It is believed that he completed this portrait in about 1791, and that it was done as a gift to one of the subject's daughters on the occasion of her marriage.