Harris was born in Jonesboro, Tennessee, in 1846 and moved to Georgia during the American Civil War to escape Union troops. At the age of sixteen, he joined the infantry of the Confederate States Army and served until the end of the American Civil War eventually becoming an officer in the 16th Virginia Cavalry. After the war, he returned to his family's home in Tennessee; however, they soon moved to Bartow County, Georgia.
After graduating college, Harris taught school for two years, studied law, and gained admittance to the state bar. He moved to Macon, Georgia in 1873. He joined with future UGA Chancellor Walter Barnard Hill to form the law firm of Hill and Harris.
Harris was elected to the Georgia House of Representatives in 1882 as a representative of Bibb County and was reelected through 1885.
Elected to the Georgia Senate from 1894 to 1895, Harris then served as judge of the Superior Court of the Macon Circuit from 1912 until his resignation in 1915 to successfully run for Governor of Georgia. He was sworn in on June 26, 1915, and served until 1917 being the last governor of Georgia born outside the state of Georgia.
He returned to his Macon law practice after his gubernatorial term and served as Pension Commissioner of Georgia from 1924 to 1925 in addition to being president of the Electoral College of Georgia.