Köl-chür

Köl-chür, known in Arabic sources as Kūrṣūl, was one of the leading Turgesh nobles under the khagan Suluk. His is chiefly known for his role in the Turgesh wars against the Umayyad Caliphate in Transoxiana, and for being responsible for the murder of Suluk in 738, precipitating the collapse of Turgesh power. He was killed either by the Arabs in 739, or by the Chinese in 744.

Life
Along with the khagan himself—usually identified with Su-Lu of the Chinese sources—Köl-chür, or "Kūrṣūl al-Turqashī" as he is found in the Arab histories, is one of only two Turgesh leaders to be mentioned by name in the Arab sources of the period. Köl-chür is usually identified with the Baga Tarkhan of Chinese sources.

He first appears in spring 721, when, following the calls for aid of the nobles of Transoxiana, he was sent to lead the first Turgesh attack on the Umayyad Arabs. Despite a setback at the fortress of Qasr al-Bahili, Köl-chür proceeded to raid deep into Transoxiana, mostly with the aid of the local population and their princes. Samarkand, which was too strong to be assaulted, was bypassed, but when at long last the unwarlike Umayyad governor, Sa'id al-Khudhayna, marched to meet him, Köl-chür inflicted a heavy defeat on the Arabs, and forced Sa'id to confine himself in the neighbourhood of Samarkand. Despite their success, however, the whole operation seems to have been, in the words of H.A.R. Gibb, "little more than a reconnaissance in force combined with a raiding expedition", and the Turgesh withdrew soon after, allowing the new Arab governor, Sa'id ibn Amr al-Harashi, to brutally suppress the local rebels and re-impose Arab authority on most of the region. He appears again in the Siege of Kamarja in 729, when he was one of the high-ranking Turgesh hostages given to the Arab garrison of Kamarja as guarantee of safe passage.

In 738/9, following the personal defeat of Suluk in the Battle of Kharistan, which greatly diminished his prestige, Köl-chür had him assassinated, possibly with Chinese backing. As a result, the Turgesh khaganate broke up into warring factions, and with its collapse "disappeared the last great Turkish confederation in Western Asia for more than two centuries to come" (Gibb), leaving the path open for the Arabs to impose their rule on Transoxiana. Köl-chür and his faction, aided by Transoxianian contingents from Ishkand, Shash and Ferghana, managed to prevail over his rivals in 739 at Suyab, but he was executed by the Chinese in 744.

Later Arab sources on the other hand attribute his capture and execution to the last Umayyad governor of Khurasan, Nasr ibn Sayyar, in 739. Gibb, however, suggests that if he is to be identified with Baga Tarkhan, this cannot possibly be true, and that this tale is probably an exaggerated re-telling of the actual capture and execution of another, lesser Turkish leader by Nasr.