The historical event that led to the establishment of the modern United Nations was the conclusion of World War II. As the war ended in 1945, the devastation and atrocities highlighted the need for an international organization to promote peace and cooperation, prevent future conflicts, and support human rights. Delegates from various nations convened in San Francisco to draft the UN Charter, which was formally established on October 24, 1945. The United Nations aimed to provide a platform for dialogue among member states, assist in humanitarian crises, and promote social and economic development, embodying a collective commitment to global peace and security.