The Charter of the United Nations was signed on June 26, 1945, in San Francisco, California, and came into effect on October 24, 1945.

The Treaty of Versailles was signed on June 28, 1919, between the Allied Powers and Germany, and officially ended World War I.

The Treaty of Rome was signed on March 25, 1957, by six European countries: Belgium, France, Germany, Italy, Luxembourg, and the Netherlands. It established the European Economic Community (EEC), which later became the European Union (EU).

The North Atlantic Treaty was signed on April 4, 1949, by twelve countries: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom, and the United States. It established NATO, a military alliance between these countries.

The Marrakesh Agreement was signed on April 15, 1994, in Marrakesh, Morocco, and came into effect on January 1, 1995. It established the WTO, which replaced GATT.

The Bretton Woods Agreement was signed on July 22, 1944, in Bretton Woods, New Hampshire, and came into effect on December 27, 1945. It established the IMF and the World Bank.

The Constitution of the World Health Organization was signed on July 22, 1946, and came into effect on April 7, 1948. It established the WHO, a specialized agency of the United Nations responsible for international public health.

The Constitution of the United Nations Educational, Scientific and Cultural Organization was signed on November 16, 1945, and came into effect on November 4, 1946. It established UNESCO, a specialized agency of the United Nations responsible for promoting international cooperation among its member states in the fields of education, science, culture and communication.

The Constitution of the International Labour Organization was adopted on April 11, 1919, as part of the Treaty of Versailles. It established the ILO, a specialized agency of the United Nations responsible for promoting social justice and improving working conditions around the world.

The Constitution of the Food and Agriculture Organization was signed on October 16, 1945, and came into effect on October 16, 1945. It established the FAO, a specialized agency of the United Nations responsible for promoting food security and agricultural development around the world.

The Convention on International Civil Aviation was signed on December 7, 1944, in Chicago, Illinois, and came into effect on April 4, 1947. It established the ICAO, a specialized agency of the United Nations responsible for promoting the safe and orderly development of international civil aviation.

The International Telegraph Convention was signed on May 17, 1865, in Paris, France, and came into effect on January 1, 1866. It established the ITU, a specialized agency of the United Nations responsible for coordinating telecommunications among its member states.

The Treaty of Bern was signed on October 9, 1874, in Bern, Switzerland, and came into effect on July 1, 1875. It established the UPU, a specialized agency of the United Nations responsible for coordinating postal services among its member states.

The Convention of the World Meteorological Organization was signed on October 11, 1947, in Washington, D.C., and came into effect on March 23, 1950. It established the WMO, a specialized agency of the United Nations responsible for coordinating meteorological services among its member states.

The Statute of the International Atomic Energy Agency was signed on October 26, 1956, in New York City, and came into effect on July 29, 1957. It established the IAEA, an autonomous intergovernmental organization responsible for promoting the safe, secure and peaceful use of nuclear energy.