Bull was born in Springfield, Massachusetts and graduated from the United States Military Academy at West Point, New York in June 1914.

[1] His fellow graduates included Carl Spaatz, Brehon B. Somervell, Charles P. Gross, John B. Anderson, James L. Bradley, Frank W. Milburn, Harold Francis Loomis, Ralph Royce, Orlando Ward, Jens A. Doe, Harry C. Ingles, and Vicente Lim, all of whom were later to achieve general officer rank.

Receiving temporary promotions to colonel and then brigadier general in July 1941, he served as assistant commander of the 4th Motorized Division at Fort Benning in Georgia from August to December 1941.

His office prepared most of the periodic situation reports to the Combined Chiefs of Staff and the SHAEF Operational Directives which were issued by Eisenhower's headquarters.

A favorable weather report by Bull's staff helped General Eisenhower decide to launch the invasion of Normandy on the morning of June 6, 1944.

[1][6] Bull died at his home in the Westmoreland Hills neighborhood of Bethesda, Maryland on November 1, 1976, and was buried at Arlington National Cemetery.