Overview
Sulu, known in Chinese sources as Su-lu and praised in Arab accounts as a valiant and tenacious opponent, was the greatest Qaghan the Türgesh Khaganate ever produced and one of the most consequential rulers in the history of Central Asia. His two-decade reign saw the Türgesh rise to the height of their power, simultaneously holding off Tang Chinese encroachment from the east, Tibetan pressure from the south, and — most significantly — the advancing armies of the Umayyad Caliphate from the west. Sulu's campaigns against the Umayyads placed him among the small number of rulers who meaningfully checked the westward advance of Arab armies across Central Asia in the early eighth century.
Arab sources called him Abu Muzahim — "the Stubborn One" or "the Butting One" — a title of reluctant respect from adversaries who found him consistently difficult to defeat. His greatest victory came on the "Day of Thirst" in 724, when he trapped an Umayyad army in Transoxiana and only a remnant reached Samarkand. At the Battle of the Defile in 731 the Arabs held the field but suffered enormous casualties, and for several years Umayyad momentum east of the Oxus stalled.
Sulu commanded loyalty through personal military ability and the distribution of plunder, and he navigated the complex multi-power competition of Central Asia with considerable strategic sophistication — balancing Tang, Tibetan, and Umayyad pressures while maintaining Türgesh independence. His assassination in 738 by one of his own commanders triggered a succession crisis that the khaganate never fully recovered from.
Rise to Power
Sulu rose to prominence in the period following the Eastern Göktürks' defeat and killing of Saqal in 711, during which the Türgesh briefly fell under Göktürk dominance. As Göktürk power itself fractured in the years following Qapaghan Qaghan's death in 716, the conditions for Türgesh reassertion emerged. Sulu — whose precise origins within the Türgesh confederation are not fully clear in the sources — was recognized as Qaghan around 717, backed by Tang China, which saw a strong Türgesh state as a useful buffer against both Tibetan and Umayyad expansion.
He received formal investiture from the Tang court and a Tang princess as a bride, cementing a relationship of nominal suzerainty that in practice left him free to act independently. From this base he rapidly established Türgesh dominance across the western steppe and launched the campaigns that would define his reign.
Rule and Achievements
- Reasserted full Türgesh independence following the period of Göktürk dominance, restoring the khaganate to sovereign status
- Conducted sustained military campaigns against the Umayyad Caliphate across the Oxus frontier, repeatedly defeating Arab armies in Transoxiana and Tokharistan
- Destroyed an Umayyad army on the "Day of Thirst" (724) and inflicted enormous casualties on the Arabs at the Battle of the Defile (731), though they held the field
- Was defeated by the Umayyad governor Asad at the Battle of Kharistan (737), the setback that preceded his murder
- Cooperated with local Sogdian and Iranian populations resisting Umayyad conquest, positioning the Türgesh as defenders of Central Asian autonomy
- Maintained working suzerain relations with Tang China while operating with full strategic independence
- Repelled Tibetan pressure on the southern approaches to the Türgesh sphere of influence
- Extended Türgesh authority across the Ili, Chu, and Syr Darya valleys at the peak of the khaganate's territorial reach
Legacy
After his defeat at Kharistan, Sulu was murdered in 738 by his relative and commander Kül Chor, known in Chinese sources by his title Baga Tarqan (Mohe Dagan). His death immediately plunged the khaganate into factional conflict between the Yellow and Black Türgesh — a division that Tang China and the Tibetans exploited to reduce Türgesh power. The khaganate never again achieved the coherence or military effectiveness of Sulu's reign.
Within the Qaghan tradition, Sulu stands as one of the defining figures of eighth-century Inner Asia — a Qaghan who met the expanding Umayyad Caliphate at the height of its Central Asian ambitions and held it. The Türgesh resistance along the Oxus, combined with the Frankish defeat of the Umayyads at Tours-Poitiers in 732, represented the two ends of the arc across which Arab expansion effectively reached its limit. Sulu's role in this broader historical moment far exceeds the subsequent obscurity of the khaganate he led.