Was appointed President Jefferson colonel of a United States regiment, which he commanded at the until 1811, when he was ordered to Washington prepare a discipline for the army. Was inspector general in 1812 and ordered to the Canadian frontier, where he failed in an invasion Canada and left the army.
He [General Smyth]...petitioned Congress to reinstate him, declaring in his memorial that he asked the privilege of "dying for his country." The phrase was ridiculed by his enemies. At a public celebration at Georgetown D.C. on Washington's birthday in 1814, the following toast was offered: "General Smyth's petition to Congress to 'die for his country'--May it be ordered that the prayer of said petitioner be granted." [Source]
There was a duel between General Smyth and General Porter.
Smyth County, Virginia, was named after the General.