The group and its four squadrons were activated without personnel or equipment on 1 June 1943, at Wendover Army Air Base, Utah. On 14 July 1943, the location of the group was changed to Gowen Field, Boise, Idaho, where a cadre of 66 officers and 237 enlisted men was assigned, transferred from the 29th Bomb Group at Gowen. Colonel Steed, formerly chief of staff of the Fourth Air Force Bomber Command, took command on the same date. While at Gowen A.A.B., and at its next two stations, the 456th received additional personnel drawn from the 18th Replacement Wing at Salt Lake City, Utah, and the 470th Bomb Group, Mountain Home AAB, Idaho. The air echelon (consisting at that time of key flying staff and four aircrews) was sent to the Army Air Force School of Applied Tactics in Orlando, Florida, for a four-week course of specialized cadre training in field operations and combat tactics.