The Lend-Lease program, initiated in 1941 during World War II, was significant for its role in supporting Allied nations, particularly Britain and later the Soviet Union, by providing military aid and supplies. This program allowed the U.S. to lend or lease war materiel, such as tanks, aircraft, and food, without direct involvement in the conflict at that time. By bolstering the defenses of crucial allies, Lend-Lease facilitated the eventual defeat of Axis powers. It marked a shift in U.S. foreign policy from isolationism towards more active engagement in global affairs, ultimately laying the groundwork for post-war international relations and the establishment of the United Nations.