The Site: Antarctica is the only continent without a native human population and is administratively governed by the Antarctic Treaty System (ATS) of 1959. Twelve countries have claims on the continent and there are over 50 research stations and 1,000 inhabitants at any given time. The land mass is 5.4 million square miles, of which ice covers 5.3 million square miles. It is a large island at the south of the planet who's inhabitants are at the mercy of the constant re-supply of food and material, making warm relations with either Argentina, South Africa, Australia or New Zealand vital to maintaining a constant human presence on the continent. Antarctica is primarily used for scientific research, with military testing being banned by the treaty as the first arms control measure of the cold war.
In 2000, an Australian scientist was poisoned while at an American base, however jurisdictional issues prevented the New Zealand authorities from questioning witnesses at the base. U.S. Marshalls are the only agency that has legal jurisdiction over American citizens living in Antarctica, while other countries maintain their own rule over their individual citizens regardless of who's territory they may be in. The only unclaimed territory is called Marie Byrd Land and is such due to its remoteness.
The Players: Current players which have territorial claims include Argentina, Chile, France, Belgium, Japan, New Zealand, Norway, South Africa, and the United Kingdom (Russia and the US have the right to make claims at anytime in the future). Many of these claims operate as a sovereign territory with their own flag, capital, and official language. The Antarctic Treaty, which aims to maintain peace between countries on Antarctica, neither supports nor denies existing claims while prohibiting new claims except in the case of US and Russia. Many claims overlap, providing the opportunity for third party exploitation in these grey areas. There is a total of 48 nations which are part of the Treaty, though those not listed above have no territorial claims on the continent.
Along with the Antarctic Treaty exists the Antarctic and Southern Ocean Coalition, which ensures that the Antarctic Continent survives as the world's last unspoiled wilderness. As opposed to the Antarctic Treaty, which is based in Argentina and acts as a political administrator to the continent, the ASOC is based in Washington D.C. and functions solely along environmental lines and is not a multilateral treaty.
Similar Multilateral Treaties:
UN Convention Law of the Sea (UNCLOS) - 1982
Outer Space Treaty - 1967
Moon Treaty - 1979
International Waters - 1857
USA Today Answers: The Antarctic treaty, territorial claims http://www.usatoday.com/weather/resources/askjack/ajackict.htm
Managing the frozen south : the creation and evolution of the Antarctic treaty system by M.J. Peterson