How and when was the united nations established

Four months after the San Francisco Conference ended, the United Nations officially began, on 24 October 1945, when it came into existence after its Charter had been ratified by China, France, the Soviet Union, the United Kingdom, the United States and by a majority of other signatories.

When: October 24, 1945, San Francisco, CA

How: Representatives of 50 nations met in San Francisco April-June 1945 to complete the Charter of the United Nations. ... The Senate approved the UN Charter on July 28, 1945, by a vote of 89 to 2. The United Nations came into existence on October 24, 1945, after 29 nations had ratified the Charter.

Explanation:

Why: The United Nations is an international organization founded in 1945 after the Second World War by 51 countries committed to maintaining international peace and security, developing friendly relations among nations and promoting social progress, better living standards and human rights.

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