The Yalta Conference in 1945 established agreements between Allied leaders Roosevelt, Churchill, and Stalin on dividing Germany into occupied zones and establishing the United Nations. The UN was formally established later in 1945. In 1948, the Universal Declaration of Human Rights was adopted, outlining fundamental human rights. NATO was formed in 1949 as a military alliance against the Soviet Union. The Warsaw Pact was formed in 1955 as a Soviet-led military alliance in response to NATO.