In the course of their expansion into Central Asia the Muslims came into contact with Turks, either settled and Iranized or else nomadic and marauding in their mode of life. As early as the time of the Caliph ‘Uthmān, when the conquest of Khurāsān was barely complete, there were, according to the historical sources, a number of incursions by Turkish nomads into that province in the neighbourhood of Marw and even as far as Nīshāpūr. Under the Umayyads, however, the Muslims came into direct contact with both the Western and the Northern Turkish states. In the period 86–96/705–15, under Qutaiba b. Muslim, the famous Umayyad governor, the Muslims won their first important victory over the Western Turks. Under Naṣr b. Sayyār, in the year 121/738–9, the Muslims broke the power of the Western Turks by defeating the dominant group amongst them, that of the TürgeshKhāqāns. The empire of the Northern Turks was destined to come to an end shortly afterwards in the year 744.