and presented the inkwell to Lincoln upon signing of the Arizona Organic Act. On 12 March 1863 Poston was appointed superintendent of Indian affairs. This appointment was followed by his election as Delegate to the U.S. House of Representatives on 18 July 1864. During his term of service, Poston submitted bills aimed at settling private land claims and to establish Indian reservations along the Colorado river. In 1865, Poston chose not to return to Arizona during his run for reelection, and was defeated by John Noble Goodwin. A final run for election to the territorial delegate position failed in 1866.