Born in Highland County, Ohio, Irwin attended the public schools.

He studied law, but abandoned the same to enlist in the Union Army during the Civil War.

Transferred to a special corps in the Regular Army, in which he served until the close of the war.

He was appointed successively assistant internal revenue assessor, deputy clerk of the United States district court, and chief deputy collector of the fifth internal revenue district of Kentucky.

This article incorporates public domain material from the Biographical Directory of the United States Congress