premise: The United Nations Charter is the foundational treaty of the United Nations, signed in 1945.
hypothesis: United Nations . The UN Charter was drafted at a conference between April -- June 1945 in San Francisco , and was signed on 26 June 1945 at the conclusion of the conference ; this charter took effect 24 October 1945 , and the UN began operation . The Charter of the United Nations ( also known as the UN Charter ) of 1945 is the foundational treaty of the United Nations , an intergovernmental organization . It was signed at the San Francisco War Memorial and Performing Arts Center in San Francisco , United States , on 26 June 1945 , by 50 of the 51 original member countries ( Poland , the other original member , which was not represented at the conference , signed it two months later ) .