142 The United Nations Organization (U.N.) was established, as is well known, on June 26, 1945. To it were subsequently added lesser organizations consisting of members nominated by the public authority of the various nations and entrusted with highly important international functions in the economics, social, cultural, educational and health fields. The United Nations Organization has the special aim of maintaining and strengthening peace between nations, and of encouraging and assisting friendly relations between them, based on the principles of equality, mutual respect, and extensive cooperation in every field of human endeavor.
Source: Pacem in Terris (Vatican.va)