United Nations is an organization.
The United Nations ( UN ) is an intergovernmental organization to promote international co-operation and to create and maintain international order . A replacement for the ineffective League of Nations , the organization was established on 24 October 1945 after World War II in order to prevent another such conflict . The organization is financed by assessed and voluntary contributions from its member states . The UN is the largest , most familiar , most internationally represented and most powerful intergovernmental organisation in the world . Some commentators believe the organization to be an important force for peace and human development , while others have called the organization ineffective , corrupt , or biased .