The Antarctic Treaty was signed in 1959 by its original 12 nations.
The treaty was signed in Washington, D.C., on 1 December 1959, after the International Geophysical Year encouraged scientific cooperation in Antarctica. It entered into force on 23 June 1961. The original signatories included Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the Soviet Union, the United Kingdom, and the United States.
The agreement established Antarctica as a region devoted to peaceful purposes and scientific investigation. It prohibits military measures such as establishing bases for warfare, conducting weapons tests, and carrying out military manoeuvres, while allowing military personnel and equipment for peaceful scientific work.
The treaty does not erase territorial claims. Instead, it freezes the position on claims: no new claim or enlargement of an existing claim may be asserted while the treaty is in force. The wider Antarctic Treaty System later added agreements on environmental protection and conservation.