inception uncok
The United Nations ( UN ) is an intergovernmental organization to promote international co - operation . A replacement for the ineffective League of Nations , the organization was established on ___MASK42___ October ___MASK82___ after World War II in order to prevent another such conflict . At its founding , the UN had 51 member states ; there are now 193 . The headquarters of the United Nations is in Manhattan , New York City , and experiences extraterritoriality . Further main offices are situated in Geneva , Nairobi , and Vienna . The organization is financed by assessed and voluntary contributions from its member states . Its objectives include maintaining international peace and security , promoting human rights , fostering social and economic development , protecting the environment , and providing humanitarian aid in cases of famine , natural disaster , and armed conflict . The UN Commission on Korea ( UNCOK ) was established in 1948 , preceding the events of the Korean War . Many of the participating nations include those who participated in the United Nations Command . The Korean War ( in South Korean , " Korean War "; in North Korean , " Fatherland Liberation War "; ___MASK5___ June ___MASK26___  27 July 1953 ) began when North Korea invaded South Korea . The United Nations , with the United States as the principal force , came to the aid of South Korea . China came to the aid of North Korea , and the Soviet Union gave some assistance .