Information taken from CIA World Factbook:
The Antarctic Treaty was opened for signature on December 1, 1959 and officially entered into force on June 23, 1961. Its objective is to ensure that Antarctica is used for peaceful purposes only (such as international cooperation in scientific research); to defer the question of territorial claims asserted by some nations and not recognized by others; and to provide an international forum for management of the region. It applies to land and ice shelves south of 60 degrees South latitude. The adoption of the treaty was a consequence of the International Geophysical Year.
There are 44 parties to the agreement: Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Chile, China, Colombia, Cuba, Czech Republic, Denmark, Ecuador, Finland, France, Germany, Greece, Guatemala, Hungary, India, Italy, Japan, North Korea, South Korea, Netherlands, New Zealand, Norway, Papua New Guinea, Peru, Poland, Romania, Russia, Slovakia, South Africa, Spain, Sweden, Switzerland, Turkey, Ukraine, UK, US, Uruguay, Venezuela