On the 15th October 1959 representatives of the twelve countries met in Washington D.C. to negotiate a treaty regarding the future of Antarctica. The twelve nations – Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the Soviet Union, the United Kingdom and the United States – were those that had undertaken scientific activity on the frozen continent during the International Geophysical Year, which lasted from July 1957 to December 1958. Poland requested to join the negotiations, having sent some scientists to the Russian Antarctic station, but this request was denied since they could sign the proposed treaty at a later date.

In the fifteen months prior to the conference, working groups had met to do much of the groundwork in a climate of cooperation that was uncommon during the Cold War. The spirit of compromise extended into the treaty negotiations. On 30th November the representatives announced that they had reached agreement on all fourteen articles of the treaty. These articles, which applied to all land and ice shelves below 60 degrees south latitude, included a ban on weapons tests on the continent, an undertaking to share scientific information, a guarantee of free movement in the area, and the empowerment of the International Court of Justice to settle and disputes.

On 1st December 1959, the treaty was opened for signatures. The governments of the twelve original nations each ratified the treaty. Chile was the last to do so, signing the treaty on the day that it came into force, 23rd June 1961. Since then representatives of thirty-four other nations have also signed the treaty.

The website of the Office of Polar Programs at the U.S. National Science Foundation includes the complete text of the 1959 treaty.