Australia claims to own the largest territory in Antarctica: 5.8 million sq km (2.2 million sq mi).
Antarctica is governed internationally through the Antarctic Treaty system.
The Antarctic Treaty was signed in 1959 by the 12 countries whose scientists had been active in and around Antarctica at the time. The negotiation of the Treaty stemmed from the very successful 1957–58 International Geophysical Year.
Among the original signatories of the Antarctic Treaty were the seven countries – Argentina, Australia, Chile, France, New Zealand, Norway, and the United Kingdom – with territorial claims to parts of Antarctica, some overlapping.
Some Treaty Parties do not recognize territorial claims and others maintain that they reserve the right to make a claim. All positions are explicitly protected in Article IV of the Antarctic Treaty, which preserves the status quo:
No acts or activities taking place while the present Treaty is in force shall constitute a basis for asserting, supporting, or denying a claim to territorial sovereignty in Antarctica or create any rights of sovereignty in Antarctica. No new claim or enlargement of an existing claim to territorial sovereignty in Antarctica shall be asserted while the present Treaty is in force.
The Antarctic Treaty puts aside the potential for conflict over sovereignty. It entered into force in 1961 and has since been acceded to by many other nations.