Qutayba’s reorganization was not confined to the civil government, however, but extended to the army as well. Hitherto the jealousy of the Arabs for their exclusive rights as a warrior caste had strictly limited the number of Persians in the armies, apart from the clients and camp followers. Thus we are told (_T_ab. 1290. 20) that the armies of Khurāsān at this period were composed as follows: from Ba_s_ra-Ahl al-ʿĀliya, 9,000; Bakr, 7,000; Tamīm, 10,000; ʿAbd al Qays, 4,000; Azd, 10,000: from Kūfa, 7,000: and alongside these 47,000 Arabs only 7,000 Mawālī, commanded by _H_ayyān-an-Naba_t_ī, who is called variously a Daylamite and a native of Khurāsān. Now, however, Qutayba imposed, first on Bukhārā, and later on each successive conquest, the obligation of providing an auxiliary corps of local troops, amounting usually to some ten or twenty thousand men, to serve with the Arab armies. It is possible, if the story be true, that this was suggested by the precedent set by Saʿīd b. ʿOthmān in the conquest of Samarqand, but more probable that it represents an entirely new departure in the East, though it had long been a practice in other spheres of the Arab conquests. We are given no hint of the motives which led to the adoption of the new system, though it would seem that they must have been of some force. Possibly it was no more than a desire to keep the native armies occupied in the service of the Arabs rather than risk a revolt in their rear. _H_ajjāj and Qutayba perhaps realised too that the Arab forces by themselves, after taking four years to reduce Bukhārā alone, were insufficient to ensure success in the greater task of subduing Samarqand. Under the new system—which recalls Pan-chʿao’s famous aphorism “Use barbarians to attack barbarians”—each conquest in turn made the next more easy. The rapidity of Qutayba’s later conquests in contrast with the early period is thus explained. It is just possible that in this plan Qutayba had an ulterior motive as well: the formation of a Persian army, trained on the same lines as the Arab forces, but more devoted to the person of the governor and able to take his part against the Arabs. How very nearly this plan succeeded, even in Qutayba’s own case, the sequel was to show.