Thomas McKean (məkān´, –kēn´), 1734–1817, political leader in the American Revolution, signer of the Declaration of Independence, b. New London, Pa. He settled at New Castle, Del., and became a lawyer and a political figure, one of the strong opponents of the British colonial system. He was (1765) a delegate to the Stamp Act Congress. McKean promoted concerted action by the colonies and was (1774–76, 1778–83) a member of the Continental Congress. Absent when the Declaration of Independence was signed, he affixed his signature later. McKean helped to frame the Delaware constitution, was president (governor) of Delaware for a short time (1777), and then was chief justice of Pennsylvania (1777–99), where he also had a home. He was (1781) briefly president of the Continental Congress and was a supporter of the Articles of Confederation, which he signed. He worked to obtain the ratification of the Constitution by Pennsylvania and was a member of Pennsylvania's state constitutional convention. A supporter of Thomas Jefferson, McKean was (1799–1808) governor of Pennsylvania. With James Wilson he wrote Commentaries on the Constitution of the United States (1792).
See studies by W. Cobbett (1798, repr. 1970) and J. H. Peeling (1929).