Thomson, Charles, 1729–1824, political leader in the American Revolution, b. Co. Londonderry (now Derry), Ireland. Emigrating to America in 1739, he later taught school and became a merchant. His pre-Revolutionary activities led John Adams to call him "the Sam Adams of Philadelphia." As secretary of the Continental Congress (1774–89), Thomson kept careful records of all proceedings and full notes of the debates. He was the moving spirit in the committee that obtained the design for the Great Seal of the United States. He wrote An Enquiry into the Causes of the Alienation of the Delaware and Shawanese Indians from the British Interest (1759), translated the Septuagint and the New Testament (4 vol., 1808), and published A Synopsis of the Four Evangelists (1815).
See biography by L. R. Harley (1900).