International Monetary Fund · Public domain

An American Treasury official who, alongside John Maynard Keynes, was a principal architect of the postwar international financial order, dominating the 1944 Bretton Woods Conference and shaping the founding of the International Monetary Fund and World Bank. He was later identified, through decoded Soviet cables from the Venona Project and post-Soviet archives, as having passed classified documents to Soviet intelligence contacts while at the Treasury — an accusation he denied under oath shortly before his death in 1948, and which remains the defining controversy of his legacy alongside his institutional achievements.