involved in drafting the United Nations Charter . The UN officially came into existence on 24 October 1945 upon ratification of the Charter by the five then-permanent members of the Security Council -- France, the Republic of China , the Soviet Union , the United Kingdom and the United States -- and by a majority of the other 46 signatories. The first meetings of the General Assembly , with 51 nations represented, and the Security Council, took place in Methodist Central Hall Westminster in London in January 1946. [ 4 ] Since its creation, there has been controversy and criticism of the United Nations . In the United States, an early opponent of the UN was the John Birch Society , which began a "get US out of the UN" campaign in 1959, charging that the UN's aim was to establish a "One World Government." After the Second World War, the French Committee of National Liberation was late to be recognized by the US as the government of France, and so the country was initially excluded from the conferences that aimed at creating the new organization. Charles de Gaulle criticized the UN, famously calling it a machin ("contraption"), and was not convinced that a global security alliance would help maintain world peace, preferring direct defence treaties between countries. [ 5 ] Legal basis of establishment Shortly after its establishment the UN sought recognition as an international legal person due to the case of Reparations for Injuries Suffered in the Service