Gerald Brown was born on December 2, 1917, in Globe, Arizona. He enlisted in the U.S. Army Air Corps on February 25, 1941, and entered the Aviation Cadet Program of the U.S. Army Air Forces on June 17, 1942.
Brown was commissioned a 2nd Lt and awarded his pilot wings at Williams Field, Arizona, on March 10, 1943, he then joined the 38th Fighter Squadron of the 55th Fighter Group, flying the P-38 Lightning. Lt Brown deployed with his unit to England in September 1943 and was credited with the destruction of 5 enemy aircraft in aerial combat plus 1 damaged. Brown then returned to the U.S. and served with a P-38 Replacement Training Group.