It was the capital of the first Uyghur Empire, built on the site of the former Göktürk imperial capital, 17 km north-to-northeast of the later Mongol capital, Karakorum.It is the ruined citadel of Khar balgas (Kara Balgasun in Turkic) is in Khotond sum on the banks of the Orkhon gol. The city was founded in AD 751 as the capital of the Uighur khanate, which ruled Mongolia from 745 to 854. Kultegiin monument, When Chinggis khaan decided to move his capital to Kharkhorin, he was well aware that the region had already been the capital to successive nomad empires. About 20 km north east of Khar Balgas lies the remainder of yet another of these pre -Mongol Empires, the Turkic khaganate (Pre- Mongol empire). Kultegin (684-731), the Khagan (ruler) of the ancient empire.