The Nāṣirī Generations 20: ASAD, SON OF SAMAN-I-KHADDAT.

20

He had four sons, Yahya, who held the territory of Shash and Isfanjab, and their dependencies; Ilyas, who held the government of the province of Hirat and parts adjacent; Ahmad, the third son, who held Samrkand and Farghanah, and their dependencies; and Nuh, the fourth, who at first held the government of Samrkand, which, however, was subsequently conferred upon Ahmad.
The Lord of the Faithful, Mamun, when he came to Marw, remarked the talents and capabilities, bravery, and innate nobility of mind of the sons of Asad, son of Saman, and he treated them with great distinction, and conferred great favours upon them, and raised them to high rank and position. When the Khalifah, Mamun, returned to Baghdad, his capital, he directed Ghassan, the son of ’Ubbad, to assume the government of Khurasan, and added thereunto the whole of it as far as Mawar-un-Nahr. Ghassan, son of ’Ubbad, made each of the sons of Asad the Amir [ruler] of a territory, and conferred certain cities upon them, as the table given at the end of this Section shows. These governments were first conferred upon them in the year 204 H.; and, when his Majesty, the Khalifah, nominated Amir Tahir-i-Zu-l-Yamanain, son of Al-Husain, to the government of Khurasan, the whole four Samani Amirs, who [as already stated] were four brothers, were confirmed by him in the territories and cities they were then holding. When the sovereignty passed from Amir Tahir to his son, Abd-ullah-i-Tahir, he confirmed the Samanis in their governments as his father had done, and made no change with respect to them.