Official dedication of the field was October 17, 1941, following the arrival of the first military members June 14. The field was named for the late Senator Morris E. Sheppard, former chairman of the Senate Military affairs Committee. Facilities were completed sufficiently to allow the first class of 22 aviation mechanics to enter training that October; the class graduated February 23, 1942.
During World War II, Sheppard conducted basic training, and it also trained glider mechanics, technical and flying training instructors and B-29 engineers. In addition to the basic flying training, the base also provided advanced pilot training for ground officers, and helicopter pilot training.
The Field reached its peak strength of 46,340 people while serving as a separation center for troops being discharged following World War II from September through November 1945.