He then returned to public service , serving on the National Defense Advisory Commission , as chairman of the War Resources Board ( 1939 ) and administrator of the Lend-Lease Program ( 1941 ) . He held the latter position until he became undersecretary of state in 1943 . The poor health of Secretary of State Cordell Hull made him chair the 1944 Dumbarton Oaks Conference and , in December 1944 , succeed Hull as Secretary of State . Stettinius was a member of the US delegation to the 1945 Yalta Conference
Yalta Conference
Yalta Conference
Edward Stettinius Jr.