His younger brother Benjamin Stephenson (1769-1822) would move to Kentucky, then the Illinois Territory, where he operated a general store and also served as a sheriff and militia leader before becoming a Congressman for the new state.
Young James Stephenson volunteered to serve in Virginia's militia, and he led a company under General Arthur St. Clair in his expedition against Native Americans in the Ohio River Valley.
He survived the ignominious St. Clair's Defeat in 1791, and, three years later, helped lead forces sent to quell the Whiskey Rebellion.
Stephenson was elected as a Federalist to the Seventeenth Congress to fill the vacancy caused by the death of Thomas Van Swearingen.
He is buried at Edge Hill Cemetery in Charles Town; a memorial was also erected to commemorate his widow, who died on January 1, 1865.