The Combined Munitions Assignments Board was a major government agency for the U.S. and Britain in World War II. With Harry Hopkins, Roosevelt's top advisor in charge, it took control of the allocation of war supplies and Lend lease aid to the Allies, especially Britain and the Soviet Union.
Churchill's original plan called for two offices for the Board, one in London which he controlled, and one in Washington under Harry Hopkins. The US Army strongly protested, and insisted that the board be under the control of the Combined Chiefs of Staff, the body that brought together the top American and British military commanders. General George C. Marshall, US Army Chief of Staff, argued that the distribution of munitions was so essential to military strategy, that it could never be left to civilians. His argument won out. Hopkins became the head of the Board, but he always saw his role as subordinate to the Combined Chiefs.
Canada asked for a seat on the Board; it was refused but was given a seat on other, much less powerful combined boards.
President Franklin D. Roosevelt and Prime Minister Winston Churchill set it up in January 1942 with a threefold mission: