McSwain was elected as a Democrat to the Sixty-seventh and to the seven succeeding Congresses and served from March 4, 1921, until his death. He served as chairman of the Committee on Military Affairs (Seventy-second through Seventy-fourth Congresses). He declined to be a candidate for renomination in 1936.
Wofford College Fitting School
University of South Carolina at Columbia
He taught school in Marlboro, Abbeville, and Anderson Counties. He studied law. He was admitted to the bar in 1901 and commenced practice in Greenville, South Carolina. Referee in bankruptcy 1912-1917. He entered the officers' training camp at Fort Oglethorpe, Georgia, May 12, 1917, and served in the First World War as captain of Company A, One Hundred and Fifty-fourth Infantry, until March 6, 1919, when he was honorably discharged. He resumed the practice of law in Greenville, South Carolina.