Drum, Augustus was born on November 26, 1815 in Greensburg, Pennsylvania, United States.
He was graduated from Jefferson College (now Washington and Jefferson), Canonsburg, Pa. He studied law.
He was admitted to the bar in 1836 and commenced practice in Greensburg. He was a member of the State senate in 1852 and 1853.
He held several local offices. He was elected as a Democrat to the Thirty-third Congress (March 4, 1853-March 3, 1855). In 1854 he was an unsuccessful candidate for reelection to the Thirty-fourth Congress.