In addition to expeditionary duty in Santo Domingo in 1923 and 1924 and in China from 1927 to 1929, Pate served at various post in the United States and Hawaii. He was promoted to first lieutenant in September 1926, to captain in November 1934, and to major in October 1938. In the spring of 1939, he became assistant chief of staff for supply, 1st Marine Division, at New River (later Camp Lejeune), North Carolina, and while there was promoted to lieutenant colonel in January 1942. He began his World War II service in this capacity, participating in the planning and combat phases of the Guadalcanal campaign. Pate was succeeded by Lieutenant Colonel Raymond P. Coffman on October 21, 1942. He was promoted to colonel in December 1943, and later saw further service in the Pacific area.