Frontiersman Patrick Gass (June 12, 1771 - April 30, 1870) was born near present Chambersburg, Pennsylvania, of Scotch-Irish parentage. At age 21 he was a ranger stationed at Yellow Creek, Ohio, and later across the Ohio River at Bennett's Fort on Wheeling Creek, Virginia, guarding the frontier against the Indians. By 1797, the Gass family had located in Brooke County. Patrick enlisted in the army in May 1799 and in the fall of 1802 was sent to Kaskaskia, Illinois Territory.

In the autumn of 1803, Capt. Meriwether Lewis arrived at Kaskaskia seeking volunteers for the Lewis and Clark expedition. Gass volunteered and was accepted. When Sgt. Charles Floyd died early in the trip, Gass was chosen by the men to replace him as one of three noncommissioned officers. Although limited in education, Sergeant Gass kept a daily account of the exploration. This journal, published in 1807, was the only complete published account of the expedition until 1814.

As a private in the War of 1812, Gass participated in the battle of Lundy's Lane and was present during the British assault on Fort Erie. In 1815, he returned home to Brooke County and spent the rest of his long life there. Although addicted to strong drink throughout much of his life he settled down and married at age 59 and thereafter sired seven children. Gass, the last survivor of the Lewis and Clark expedition, died at age 98 and is buried at Wellsburg.