Ötüken or Otuken (Old Turkic: 𐰇𐱅𐰜𐰤:𐰖𐰃𐱁, romanized: Ötüken yïš, lit. 'Ötüken forest' or 𐰵𐱅𐰜𐰤:𐰘𐰼, romanized: Ötüken jer, lit. 'land of Ötüken'; Old Uighur: 𐰵𐱅𐰜𐰤:𐰘𐰃𐱁, romanized: Ötüken yïš; Chinese: 於都斤) was the capital of the First Turkic Khaganate, the Second Turkic Khaganate and the Uyghur Khaganate. It has an important place in Turkic mythology and Tengrism.
Ötüken is located within the borders of the Arkhangai Province and Övörkhangai Province of present-day Mongolia.
The Second Turkic Khaganate was a khaganate in Central and Eastern Asia founded by Ilterish of the Ashina clan of the Göktürks and lasted from 682 to 744. It was preceded by the Eastern Turkic Khaganate (552–630) and the early Tang dynasty period (630–682). The Second Khaganate was centered on Ötüken in the upper reaches of the Orkhon River. It was succeeded by its subject Toquz Oghuz confederation, which became the Uyghur Khaganate.
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