The international organization established after World War II to prevent future conflicts is the United Nations (UN). Founded in October 1945, the UN aimed to foster international cooperation and promote peace, security, and human rights worldwide in the wake of the devastating effects of the war. Its creation was a response to the need for a platform where nations could come together to address global challenges, mediate disputes, and prevent atrocities like those experienced during the war. The UN has been instrumental in various peacekeeping efforts and humanitarian initiatives globally.