John Thomas Glenn (April 21, 1844March 14, 1899) was the 31st Mayor of Atlanta from 1889 to 1891, and the son of another Atlanta mayor, Luther Glenn, and like his father an attorney at law. At the beginning of the American Civil War he was attending the University of Georgia where he received a Bachelor of Arts degree just before the institution was shut down in September 1863. He then served as a captain in the Confederate army.