Indeed, events were opening the way slowly, but surely, to their ascendency. Throughout the whole of the tenth century, which followed, they seem to disappear from history; but a silent revolution was all along in progress, leading them 5 forward to their great destiny. The empire of the Caliphate was already dying in its extremities, and Sogdiana was one of the first countries to be detached from his power. The Turks were still there, and, as in Persia, filled the ranks of the 10 army and the offices of the government; but the political changes which took place were not at first to their visible advantage. What first occurred was the revolt of the Caliph's viceroy, who made himself a great kingdom or empire out 15 of the provinces around, extending it from the Jaxartes, which was the northern boundary of Sogdiana, almost to the Indian Ocean, and from the confines of Georgia to the mountains of Afghanistan. The dynasty thus established 20 lasted for four generations and for the space of ninety years. Then the successor happened to be a boy; and one of his servants, the governor of Khorasan, an able and experienced man, was forced by circumstances to rebellion against him. 25 He was successful, and the whole power of this great kingdom fell into his hands; now he was a Tartar or Turk; and thus at length the Turks suddenly appear in history, the acknowledged masters of a southern dominion. 30