Adamson Tannehill (May 23, 1750 – December 23, 1820), a native of Maryland, is representative of the United States’ founding generation whose members were active participants in the early military and political events of their country's establishment. He was among the first volunteers to join the newly established Continental Army during the American Revolutionary War. He served for five and a half years, ultimately achieving the rank of captain and commander of the army's longest serving rifle unit. After the war, Tannehill and members of his family settled in Pittsburgh, his last military post of the conflict. He was an early leading citizen of Pittsburgh and a distinguished Pennsylvania politician who held several local and state appointed and elected offices, including one term as a U.S. Congressman; served on the founding boards of civic, state, and national organizations; and had prominent military roles in the state's post-Revolutionary War years. Early years Adamson Tannehill was born in Frederick County, Maryland, probably close to Frederick Town (now Frederick). He was the oldest of nine children born to John Tannehill, owner of a tobacco plantation, and Rachel Adamson. His maternal grandfather took a special interest in the grandchild who bore his name, and he provided funding to secure a fine education for Adamson. Little else is known of Adamson's earliest years. No known portraits of Tannehill exist; however, family records indicate that as an adult he “was six feet in height, well proportioned and of commanding appearance.” At the age of 25, he enlisted in one of the first American military units to form when the war with Great Britain started in the spring of 1775. Revolutionary War service Tannehill served in the Continental Army during the American Revolutionary War, initially as the first sergeant in Capt. Thomas Price's Independent Rifle Company, one of the original ten independent companies of riflemen from the frontier regions of Pennsylvania, Maryland, and Virginia authorized by the Continental Congress on June 14, 1775. He received his commission dated January 1, 1776, as a third lieutenant while serving at the Siege of Boston. In June 1776 Tannehill and his company were incorporated into the newly organized Maryland and Virginia Rifle Regiment, at which time he advanced to second lieutenant. Later that year a large portion of his regiment was captured or killed at the Battle of Fort Washington on northern Manhattan Island. However, those members of the unit