December 1, 1959

Antarctic Treaty System

Twelve states sign the Antarctic Treaty in Washington

Its military clause has a counterintuitive second sentence: soldiers and military equipment may still go to Antarctica, provided the purpose is science or something else peaceful.

The last day of the Conference on Antarctica

On 1 December 1959, at the close of a conference that had run in Washington since 15 October, representatives of twelve states signed the Antarctic Treaty. Herman Phleger, head of the U.S. delegation, chaired the conference.

The signatories were Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the Soviet Union, the United Kingdom and the United States. The United States and the Soviet Union accepted the same inspection regime while the Cold War was intensifying.

The text reserved Antarctica for peaceful purposes and prohibited military bases, fortifications, maneuvers and weapons testing — while expressly allowing military personnel and equipment to support scientific or other peaceful work.

Claims frozen, not settled

Seven of the twelve had territorial claims, some overlapping. The treaty preserved every party's existing position on sovereignty and barred new or enlarged claims while it remained in force, without recognizing, settling or extinguishing anything.

It protected freedom of scientific investigation and provided for exchanging scientific plans, personnel, observations and results.

It prohibited nuclear explosions and radioactive-waste disposal, and opened stations, installations and equipment to inspection — a right consultative parties could exercise, not a mandatory schedule.

Words the 1959 text does not contain

The treaty does not call Antarctica a "scientific preserve" or a "natural reserve." That language comes from the 1991 Environmental Protocol, which took effect in 1998.

Nor did the United States abandon a claim: it had never asserted a formal territorial claim, and it retained its basis-of-claim position under Article IV.

Signature did not make the treaty operative. It entered into force on 23 June 1961, once all twelve ratifications had been deposited.

Sources

Researched 24 Aug 2026 6 sources not yet audited

How this was checked

Researched from the web into a fact sheet and rewritten from that sheet. This article has not yet had an independent model audit. How the pipeline works →

What the sources leave uncertain

The signing date, place and parties are certain.
Calling this categorically the 'first Cold War arms-control agreement' is classificatory rather than a treaty fact. U.S. sources call it the earliest postwar arms-limitation agreement or say it is sometimes referred to as the Cold War's first arms-control agreement.