The Tahirid dynasty was a dynasty, of Persian Dehqan origin, that effectively ruled the Khorasan from 821 to 873 while other members of the dynasty served as military and security commanders for the city of Baghdad from 820 until 891. The dynasty was founded by Tahir ibn Husayn, a leading general in the service of the Abbasid caliph al-Ma’mun. Their capital in Khorasan was initially located at Merv but was later moved to Nishapur. The Tahirids have been described as the first independent Iranian dynasty after the fall of the Sassanian Empire. However, according to Hugh Kennedy: “The Tahirids are sometimes considered as the first independent Iranian dynasty, but such a view is misleading. The arrangement was effectively a partnership between the Abbasids and the Tahirids.” Instead, the Tahirids were loyal to the Abbasid caliphs and enjoyed considerable autonomy rather than being independent of the central authority. The tax revenue from Khorasan that was sent to the caliphal treasury was perhaps larger than those collected previously.

Rise

The founder of the Tahirid dynasty was Tahir ibn Husayn, a general who had played a major role in the civil war between the rival caliphs al-Amin and al-Ma’mun. He and his ancestors had previously been awarded minor governorships in eastern Khorasan for their service to the Abbasids. In 821, Tahir was made governor of Khorasan, but he died soon afterwards. The caliph then appointed Tahir’s son, Talha, whose governorship lasted from 822–828. Tahir’s other son, Abdullah, was instated as the wali of Egypt and the Arabian Peninsula, and when Talha died in 828 he was given the governorship of Khorasan. Abdullah is considered one of the greatest of the Tahirid rulers, as his reign witnessed a flourishing of agriculture in his native land of Khorasan, popularity in the eastern lands of the Abbasid caliphate and expanding influence due to his experience with the western parts of the caliphate.

The replacement of the Pahlavi script with the Arabic script in order to write the Persian language was done by the Tahirids in 9th century Khurasan.

Fall

Abdullah died in 845 and was succeeded by his son Tahir II. Not much is known of Tahir’s rule, but the administrative dependency of Sistan was lost to rebels during his governorship. Tahirid rule began to seriously deteriorate after Tahir’s son Muhammad ibn Tahir became governor, due to his carelessness with the affairs of the state and lack of experience with politics. Oppressive policies in Tabaristan, another dependency of Khorasan, resulted in the people of that province revolting and declaring their allegiance to the independent Zaydi ruler Hasan ibn Zayd in 864. In Khorasan itself, Muhammad’s rule continued to grow increasingly weak, and in 873 he was finally overthrown by the Saffarid dynasty, who annexed Khorasan to their own empire in eastern Persia.