Ya`kūb soon set upon a career of extended conquest, and made himself master of Herāt (A.H. 253 (867)), Kirmān, and Shīrāz. In A.H. 257 (871) he sent a message to Muwaffak, the Caliph Mu`tamid’s brother, declaring himself one of the Caliph’s most humble slaves, and proposing to pay him a visit. The Caliph, wishing at any cost to keep this redoubtable warrior at a safe distance, sent him an investiture of the government of Balkh, Tokhāristān, and all the country as far as the Indian frontier. These districts were inhabited by widely different races, and included the Turks of Kābul and their neighbours the Afghans. Ya`kūb now crossed the passes of the Hindu Kush and entered the Kābul valley. For the past hundred years or so it had never entered the mind of any Eastern governor to disturb the independence of the Turkish king of Kābul.[222] But Ya`kūb succeeded where the early Moslem conquerors had failed, for he carried off the king and all his idols, and was the first to establish Islām in a district hitherto under the influence of Buddhism. In A.H. 259 (872) he administered a crushing defeat to the last of the Tāhirides, and thus became master of Khorāsān and the East. He died in A.H. 265 (878), leaving nearly the whole of Persia to his brother `Amr, who for some years enjoyed a prosperous rule and remained obedient to the Caliph at Baghdād. But in A.H. 271 (884), owing to the complaints of the inhabitants of Khorāsān, the Caliph Mu`tamid deprived `Amr of the governorship of that province, which was apparently given to Rāfi` ibn Harthama, and sent an army to attack him. In the first encounter `Amr was defeated, and fled to his native state of Sīstān by way of Shīrāz and Kirmān. At this point we must for a time leave `Amr, and revert to the story of the Sāmānides. [Illustration: A JEWISH CHILD OF BOKHĀRĀ]