Abu'l-Abbas Muhammad ibn Abdallah ibn Tahir (Arabic:محمد بن عبدالله بن طاهر) (824/5 – November 867) was aTahirid family member, who served theAbbasid Caliphate as governor and chief of police (sahib al-shurta) ofBaghdad from 851 until his death, during a particularly troubled period in the city's history, which included its siege during thecivil war of 865–866, in which he played a major role. He also served in the 860s as governor ofBaghdad,Mecca andMedina, and was noted as a scholar, a poet and a patron of artists and scholars.

Muhammad was born in 824/5 (AH 209).^[1] He was the son ofAbdallah ibn Tahir al-Khurasani, who after a distinguished military career became military governor (wali al-harb wa'l-shurta) ofBaghdad, before going on to rule a vast viceroyalty in the East, comprising central and easternIran, from 830 to 845; according toC.E. Bosworth, he was "perhaps the greatest of the Tahirids". Baghdad and the family's interests inIraq remained in the hands of his cousin,Ishaq ibn Ibrahim and his heirs.^[2][3] In the East, Abdallah was succeeded by his sonTahir, but in Iraq, the family's position was far less stable, as the Tahirids there quarrelled among themselves.^[4] As a result, in 851 the Caliphal-Mutawakkil called Muhammad ibn Abadallah fromKhurasan to Iraq, where he assumed the governorships of Baghdad, theSawad andFars, while according to the 10th-century Egyptian scholaral-Shabushti, he also served as the caliphs' chamberlain (hajib).^[5]

Shortly after the accession ofal-Musta'in in 862, Tahir ibn Abdallah died. Musta'in proposed that Muhammad take up his brother's viceroyalty in the East, but he refused, and Tahir's sonMuhammad was named instead. Muhammad ibn Abdallah was reconfirmed in his old offices, and received in addition the governorship ofMecca andMedina.^[1][5] The next years were troubled for the Caliphate as it entered aperiod of domestic instability that paralysed its government.^[6] Riots broke out in Baghdad in 863 on the news of a majorByzantinevictory against the Muslims, which necessitated the intervention of Turkish troops before they could be suppressed,^[1] while in 864, Muhammad ibn Abdallah had to suppress anAlid uprising that broke out inKufa underYahya ibn Umar, who defeated the first army sent against him before being encircled and killed by the generalHusayn ibn Isma'il in August.^[1][5]Iraq Ajami, along with the provinces on the southern shore of theCaspian Sea, also came under Muhammad ibn Abdallah's jurisdiction. In the latter,Gurgan andTabaristan, he had appointed his brotherSulayman, whose administration was so oppressive that the local people rose in revolt in 864 and invited another Alid,Hasan ibn Zayd, to lead them. Although caliphal forces managed to defeat the initial uprising and drive Hasan and his supporters to the mountains ofDaylam, in the early 870s he managed to recover Tabaristan, establishing anindependent Alid dynasty in the region.^[7][1] InArabia too, Alid elements used the turmoil in Iraq to rise in revolt: in 865, an Alid named Isma'il ibn Yusuf plundered both Mecca and Medina, killing so many of the pilgrims who had gathered there for thehajj, that he was nicknamedal-Saffak, "the Bloodshedder".^[1]

In the same year, the civil strife in the Abbasid court reached Baghdad itself: in February 865, Musta'in leftSamarra along with the Turkish generalsWasif andBugha the Younger and sought refuge in Baghdad. Back in Samarra, the rest of the Turkic military establishment raisedal-Mu'tazz to the throne, and under the command of the new caliph's brother,Abu Ahmad, marched on Baghdad. Thesiege of Baghdad by the Samarran troops lasted for almost the entire year, and Muhammad ibn Abdallah led the defence in support of al-Musta'in. Gradually however he despaired of any prospects for victory, and began negotiations with Abu Ahmad. He was accused of treason and almost lynched by the city's defenders, and was saved only by the intervention of al-Musta'in. Eventually, al-Musta'in agreed to surrender and abdicate in favour of Mu'tazz in January 866.^[1][8][9] Muhammad remained in his position and held his offices until his death in November 867.^[1]

Among contemporaries, he was also known as a scholar and poet. He relatedhadiths, and was a patron of artists like the singer Ahmad ibn Yahya al-Makki, called Zunayn, who wrote hisKitab mujarrad fi'l-aghani ("Book of Choice Songs") for him. He also had a "lively interest in grammar and philology" (Bosworth), with the prominent grammariansal-Mubarrad andTha'lab frequenting his circle and engaging in disputations in his presence.^[1][10]

• 820s births
• 867 deaths
• Tahirid governors of Baghdad
• Poets from the Abbasid Caliphate
• 9th-century Iranian people
• Persian-language poets
• Abbasid governors of Mecca
• Abbasid governors of Medina
• Abbasid governors of Iraq
• 9th-century people from the Abbasid Caliphate

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