During World War II, he commanded the New Hebrides Task Force, Southwestern Security District, and Fort Ord.

[1][8] A highlight of Chamberlin's football career was his pickup of a fumbled Navy punt and 92 yard return during the 1908 Army-Navy game, which set up his three-yard run for the touchdown that enabled Army's 6–4 victory.

[4] In June 1918, Chamberlin was assigned to the 152d Depot Brigade at Camp Upton, New York and promoted to temporary major.

[11] After the war, Chamberlin remained in France as an instructor at First United States Army's School for the Care of Animals.

[11] In March and April, Chamberlin carried out an inspection trip in England, France, Belgium, and Germany, on which he visited British cavalry regiments and remount depots to learn their animal care techniques.

[11] During the spring of 1919, Chamberlin trained in Koblenz prior to participating in the Inter-Allied Games, which took place in Paris that summer.

[4] After graduating in early 1923, he enrolled in the Italian Cavalry School at Tor di Quinto, where he completed the program of instruction in late 1923.

[12] During his return to the United States, Chamberlin spent time in England during 1924 as an observer at the Army School of Equitation, Weedon.

[4] From 1926 to 1927, Chamberlin attended the United States Army Command and General Staff College, and he completed the course as an honor graduate.

[4] After graduating, he was assigned to command 1st Squadron, 14th Cavalry Regiment at Fort Sheridan, Illinois and the Civilian Conservation Corps' Wisconsin-based 10th Forestry District.

[4] As the United States prepared for entry into World War II, Chamberlin commanded the 2nd Cavalry Regiment at Fort Riley from 1939 to 1941.

[4] In 1942, Chamberlin commanded the combined services task force which occupied New Hebrides and defended the islands against attack from Japan.

[1][16] Doctors attempted to treat Chamberlin as he commanded first the Southwestern Security District and later Fort Ord, but his illness proved to be terminal.

[19] They divorced in 1933, and later that year Chamberlin married Helen Elena Bradman, the daughter of United States Marine Corps Brigadier General Frederic L.

[21] During World War II, Sally Garlington Chamberlin was employed as General George C. Marshall's private secretary.