Kazakhstan (/ˌkɑːzəkˈstɑːn/ or /ˌkæzəkˈstæn/; Kazakh: Қазақстан Qazaqstan, قازاقستان, pronounced [qɑzɑqstɑ́n]; Russian: Казахстан [kəzɐxˈstan]), officially the Republic of Kazakhstan, is a contiguous transcontinental country in Central Asia, with its smaller part west of the Ural River in Europe. Kazakhstan is the world's largest landlocked country by land area and the ninth largest country in the world; its territory of 2,727,300 square kilometres (1,053,000 sq mi) is larger than Western Europe. It has borders with (clockwise from the north) Russia, China, Kyrgyzstan, Uzbekistan, and Turkmenistan, and also adjoins a large part of the Caspian Sea. The terrain of Kazakhstan includes flatlands, steppe, taiga, rock canyons, hills, deltas, snow-capped mountains, and deserts. With 17 million people (2013 estimate) Kazakhstan has the 62nd largest population in the world, though its population density is less than 6 people per square kilometre (15 people per sq. mi.). The capital is Astana, where it was moved from Almaty in 1997.The territory of Kazakhstan has historically been inhabited by nomadic tribes. This changed in the 13th century, when Genghis Khan occupied the country. When his ruling family fought for power, power generally switched back to the nomads. By the 16th century, the Kazakhs emerged as a distinct group, divided into three jüz (ancestor branches occupying specific territories). The Russians began advancing into the Kazakh steppe in the 18th century, and by the mid-19th century all of Kazakhstan was part of the Russian Empire. Following the 1917 Russian Revolution, and subsequent civil war, the territory of Kazakhstan was reorganized several times before becoming the Kazakh Soviet Socialist Republic in 1936, a part of the Soviet Union.Kazakhstan was the last of the Soviet republics to declare independence following the dissolution of the Soviet Union in 1991; the current President, Nursultan Nazarbayev, has been leader of the country since 1991. Nazarbayev maintains strict control over the country's politics. Since independence, Kazakhstan has pursued a balanced foreign policy and worked to develop its economy, especially its hydrocarbon industry.Kazakhstan is ethnically and culturally diverse, in part due to mass deportations of many ethnic groups to the country during Joseph Stalin's rule. Kazakhstan has a population of 17.7 million, with 131 ethnicities, including Kazakh, Russian, Ukrainian, German, Uzbek, Tatar, and Uyghur. Around 63% of the population are Kazakhs. Kazakhstan allows freedom of religion. Kazakhstan has been quite a religiously tolerant nation, but has lately come under international criticism for lack of religious freedom. Robert George, the chairman of the U.S. Commission on International Religious Freedom stated in 2013: "the harsh application of highly restrictive laws that were adopted two years ago, have [sic] damaged Kazakhstan's international standing and resulted in many Kazakh citizens' religious freedoms being violated." Islam is the religion of about 70% and Christianity is practiced by 26% of the population. The Kazakh language is the state language, while Russian has equal official status for all levels of administrative and institutional purposes.