John was from Wales, a son of William and Elizabeth Thomas Harris. He crossed the Atlantic on the ship Ellen Maria in 1851. On the ship manifest his occupation is given as "miner." In his autobiography he says that he crossed the plains in the Jesse Crosby Company; Crosby was president of the Atkins Company of 1853. John was re-baptized at Salt Lake City on 17 September 1853 and received a Patriarchal Blessing on 11 November this same year. He labored on Public Works off and on in 1853, 1854, 1855. He was a member of the 37th Quorum of Seventy of which Jesse W. Crosby was a president. At the time of the 1856 Utah Territorial census he was living in Cedar City.