sometimes poetically called the "Land of Eternal Blue Sky" () by its inhabitants. According to some scholars, the name of the important deity Dangun (also Tangol) (God of the Mountains) of the Korean folk religion is related to the Siberian Tengri ("Heaven"), while the bear is a symbol of the Big Dipper (Ursa Major). The word "Tengrism" is a fairly new term. The spelling Tengrism for the religion of the ancient Turks is found in the works of the 19th century Kazakh Russophone ethnographer Shoqan Walikhanov. The term was introduced into a wide scientific circulation in 1956 by Jean-Paul Roux and later in the 1960s as a general term of English-language papers. Tengrianism is a reflection of the Russian term, ("Tengriánstvo"). It is introduced by Kazakh poet and turkologist Olzhas Suleymenov in his 1975 book AZ-and-IA. Since the 1990s, Russian-language literature uses it in the general sense, as for instance, reported in 1996 ("so-called Tengrianism") in the context of the nationalist rivalry over Bulgar legacy. The spellings Tengriism, Tangrism, Tengrianity are also found from the 1990s. In modern Turkey and, partly, Kyrgyzstan, Tengrism is known as the or ("Sky God religion"); the Turkish (sky) and (God) correspond to the Mongolian (blue) and (sky), respectively. Mongolian is used in a 1999 biography of Genghis Khan. In the 20th century, a number of scientists proposed the existence of a religious imperial khagan cult in the ancient Turkic and Mongolian states. The Turkish historian of religion Ziya Gökalp (1876–1924) wrote in his The History of Turkish Holy Tradition and Turkish Civilization that the religion of the ancient Turkic states could not be primitive shamanism, which was only a magical part of the religion of the ancient Türks (see a historiography of the problem: ). The nature of this religion remains debatable. According to many scholars, it was originally polytheistic, but a monotheistic branch with the sky god Kök-Tengri as the supreme being evolved as a dynastical legitimation. It is at least agreed that Tengrism formed from the diverse folk religions of the local people and may have had diverse branches. It is suggested that Tengrism was a monotheistic religion only at the imperial level in aristocratic circles, and, perhaps, only by the 12th-13th centuries (a late form of development of ancient animistic shamanism in the era of the Mongol empire). According to Jean-Paul Roux, the monotheistic concept evolved later out of a polytheistic