Terra Nullius

Terra nullius ( /ˈtɛrə nʌˈlaɪ.əs/, plural terrae nullius) is a Latin expression deriving from Roman law meaning "land belonging to no one", which is used in international law to describe territory which has never been subject to the sovereignty of any state, or over which any prior sovereign has expressly or implicitly relinquished sovereignty. Sovereignty over territory which is terra nullius may be acquired through occupation, though in some cases doing so would violate an international law or treaty.