He was appointed to the United States Military Academy at West Point and in 1932 he graduated and was commissioned in the cavalry.
From 1946 to 1948, he served on the staff of the Caribbean Command in the Panama Canal Zone, beginning a long association with Latin America.
Mather's awards and decorations included the Army Distinguished Service Medal with oak leaf cluster, the Legion of Merit, the Bronze Star Medal with "V" device, the Purple Heart, the Combat Infantryman Badge and the Ordem do Mérito Aeronáutico from Brazil, provided for service, in 1964.
Mather retired to Pinehurst, North Carolina, and served two terms as a village councilman.
He died on 1 January 1993, in Southern Pines, North Carolina, survived by a son and daughter.