There are hundreds of currently active international treaties, with participation ranging from two states to more than 95% of all nations on Earth. Many modern treaties are administered under the auspices of the United Nations. Some treaties are associated with independent watchdog bodies whose mission is to ensure the treaty is honored.
International treaties date back at least to 1258 BC, when the Egyptian pharaoh Ramses II and the Hittite monarch Hattusili III made a peace agreement in the wake of the Battle of Kadesh, the greatest chariot battle in history. Originally inscribed on a silver tablet, a fragmented clay copy survives to this day, and can be viewed at the Istanbul Archaeology Museum.
Hundreds, if not thousands, of international treaties were signed in the ancient world, throughout the Middle Ages and the Renaissance, mostly to end wars, forge territorial agreements, and guarantee economic and military support among allies.
One of the most-cited international treaties today are the Geneva Conventions. There have been four Geneva Conventions, in 1864, 1906, 1929, and 1949. The Geneva Conventions deal with the treatment of battlefield casualties, prisoners of war, and civilians during wartime. The Geneva Conventions provide a diplomatic framework for protecting non-combatants and allowing the recovery of wounded by the battlefield, by designated groups flying the Red Cross, Red Crescent, or Red Crystal emblem.
The international treaty known as the UN Charter established the United Nations in 1945, in the wake of World War II. This was followed by the North Atlantic Treaty in 1949, which established the military alliance NATO, and the Treaty of London in the same year, establishing the Council of Europe. 1955 saw the signing of the Warsaw Pact, a famous alliance between eastern European states and the Soviet Union which helped start the Cold War.
In 1959, the Antarctic Treaty was signed, designating Antarctica as a research area, forbidding military activity there, and splitting it into slices for several dozen countries. In 1961, the Convention on the Reduction of Statelessness was signed, designed to bring into effect policies which would protect people without nationality. In 1963, the famous Partial Test Ban Treaty was signed, forbidding any nuclear tests except for underground, followed by the Anti-Ballistic Missile Treaty in 1972, designed to limit the deployment of ballistic missiles, and the Threshold Test Ban Treaty in 1974 which forbade testing of all nuclear weapons with a yield of over 150 kilotons. All of these treaties had important implications for the Cold War. 1996 saw the Comprehensive Test Ban Treaty, meant to ban nuclear explosions worldwide for any purpose, but it has not yet been ratified, and requires signatures of countries such as the United States, North Korea, and Iran before it will enter into force.
Several important international treaties involving weapons of mass destruction and military buildup have been signed. These include the Biological Weapons Convention, the Chemical Weapons Convention, and the Treaty on Conventional Armed Forces in Europe.