Kazakhstan, part of the USSR from 1922 until 1991, is an independent republic in Central Asia, bounded by Russia, China, Kyrgyzstan, Uzbekistan, Turkmenistan, and the Caspian Sea. Located principally in Asia, with a small portion west of the Ural River in Europe, Kazakhstan has served as a major intersection of varying cultures and empires—notably those of the Russians and Mongols. Kazakhs, the largest ethnic group, constitute a majority of the population. The majority of the population is Muslim. Following its independence from the USSR, the new republic voluntarily gave up the nuclear weapons that were stationed on its territory. Known for its natural resources, including oil, Kazakhstan has positioned itself as a magnet for strategic economic investment in Central Asia.