not taken in the battle, including Tannehill, continued to serve actively with Washington's Main Army, participating in the Battles of Trenton and Princeton, and in the spring of 1777 were administratively attached to the 11th Virginia Regiment. Tannehill was promoted to first lieutenant on May 18, 1777, and the following month he was attached to the newly organized Provisional Rifle Corps commanded by Col. Daniel Morgan, which played a major role in the Battles of Saratoga and a peripheral role in the Battle of Monmouth. He returned to the Maryland and Virginia Rifle Regiment (his permanent unit) in mid-1778 when Lt. Col. Moses Rawlings, the regiment's commander who had been exchanged from British captivity earlier that year, was marshaling the remnants of his unit and recruiting new members while stationed at Fort Frederick, Maryland. In early 1779 Tannehill and the regiment were assigned to Fort Pitt of present-day western Pennsylvania where they supplemented other Continental forces engaged in the defense of frontier settlements from Indian raids. Tannehill advanced to the rank of captain on July 29, 1779, and he commanded the regiment in late 1780. He was discharged from service on January 1, 1781, when his unit was disbanded, and was admitted as an original member of The Society of the Cincinnati in the state of Maryland when it was established in 1783. Early Pittsburgh After the war Tannehill settled in Pittsburgh, as did a number of other Revolutionary War officers, including his brother Lt. Josiah Tannehill. He initially engaged in agricultural pursuits and was a tavern owner and vintner, president of the Pittsburgh Fire Co., and a trustee of the first Presbyterian church in Pittsburgh. He later served as a local Justice of the Peace; lieutenant colonel of Westmoreland Co. militia starting in 1788; an original member of the Board of Directors of the Pittsburgh branch of the Bank of Pennsylvania, the first bank in Pittsburgh, starting in 1804; one of five turnpike commissioners for the state starting in 1811; major general of Pennsylvania Volunteers during the War of 1812; and president of the Pittsburgh branch of the Bank of the United States starting in 1817. The high point of Tannehill's active political career was his election as a Republican to the Thirteenth U.S. Congress for the period 1813–1815. He was an unsuccessful candidate for reelection in 1814 to the Fourteenth Congress. In October 1800, Tannehill was temporarily removed