Isaac D. Shadd (1829 – March 15, 1896) was a newspaper publisher, printer, politician, and bookkeeper. Before the American Civil War, he and his sister Mary Ann Shadd moved to Chatham, Ontario, and published the anti-slavery newspaper, The Provincial Freeman. He and his wife taught at the Chatham Mission School. He was involved in the planning of the John Brown's raid on Harpers Ferry and led the Chatham Vigilance Committee to rescue Sylvanus Demarest in 1858. He returned to the United States and served as a member of the Mississippi House of Representatives during the Reconstruction era from 1871 until 1876. From 1874 to 1875, he was the Speaker of the House.