Ubaydallah ibn al-Sari
عبيد الله بن السري
Gold dinar minted in Egypt in 823/4, displaying the names of the caliph al-Ma'mun and Ubaydallah ibn al-Sari
Governor of Egypt
In office 822–826
Monarch	Al-Ma'mun
Preceded by	Abu Nasr ibn al-Sari
Succeeded by	Abdallah ibn Tahir al-Khurasani
Personal details
Born	unknown
Died	April 865 Samarra
Parent	Al-Sari ibn al-Hakam Al-Zuti

Ubaydallah ibn al-Sari (Arabic:عبيد الله بن السري) (died 865) was a governor ofEgypt from 822 until 826. A son ofal-Sari ibn al-Hakam, he was the third and last member of his family to autonomously rule over parts of Egypt during the troubled period following thegreat Abbasid civil war, and his surrender toAbdallah ibn Tahir in 826 marked the re-imposition of firmAbbasid control over the province for the first time since the outbreak of the conflict.

Ubaydallah was the son ofal-Sari ibn al-Hakam, aZutt member of theabna al-dawla,^[1][2] who had served as governor of Egypt in 816 and 817–820. Following the death of al-Sari in 820 Ubaydallah was appointed as prefect ofpolice by his brotherAbu Nasr,^[3] who had assumed the governorship, and upon Abu Nasr's own death in 822 he was himself acclaimed as his successor and given theoath of allegiance by the army. As a result of the division of Egypt under his father, however, his effective jurisdiction extended only to the capitalFustat and the southern part of the province, while much ofLower Egypt was in the hands of Ali ibn Abd al-Aziz al-Jarawi andAndalusian raiders.^[4]

Ubaydallah's rule over Egypt was initially contested by the Abbasid central government, which was still attempting to recover from the loss of authority it had incurred due to thecivil war between the rival caliphsal-Amin andal-Ma'mun in 811–813, and shortly after his accession he was forced to deal with an invasion byKhalid ibn Yazid al-Shaybani, who had been delegated by al-Ma'mun to seize command of the country. Ubaydallah decided to offer resistance, and even with Ibn al-Jarawi providing assistance to Khalid he was able to win a battle against the latter on the outskirts of Fustat. Over the next few months the two sides fought several engagements; at length Ibn al-Jarawi withdrew his support and Khalid's position became seriously degraded, and by early 823 he was finally defeated and captured by Ubaydallah. His hold over Fustat now secure, Ubaydallah returned to the capital and afterwards released Khalid, allowing him to withdraw from the province toMecca.^[5]

Following the end of Khalid's campaign, Ubaydallah became focused on dealing with his rival Ibn al-Jarawi, who continued to hold Lower Egypt. Although al-Ma'mun had written to both men granting them the right to collect theland taxes in the areas they respectively controlled, the two sides quickly found an excuse to come into conflict with each other and war soon broke out. Over the course of the next several years Ubaydallah's forces invaded Lower Egypt, pillaging Mahallat al-Sharqiyun and repeatedly occupyingTinnis andDamietta, and Ibn al-Jarawi was at times forced to seek refuge in the towns along the northernSinai. Despite this Ubaydallah was unable to fully defeat his opponent, and the latter was able to make a return to the region in mid-825.^[6]

Ubaydallah's governorship came to an end in 826, when al-Ma'mun again sought to achieve greater effective control over the country by dispatching to it theTahirid generalAbdallah ibn Tahir. While Ibn al-Jarawi immediately offered his submission, Ubaydallah attempted to fight off Abdallah, but his forces were defeated and he eventually decided to seek a guarantee of safety instead. This was agreed to and Ubaydallah made his submission to Abdallah, who sent him off toBaghdad.^[7] Following this, he never returned to Egypt, but he remained inIraq and eventually died inSamarra in 865.^[8]

The construction of theAl-Sayyida Nafisa Mosque is attributed to him.^[9]

• Bosworth, C. E., ed. (1987).The History of al-Ṭabarī, Volume XXXII: The Reunification of the ʿAbbāsid Caliphate: The Caliphate of al-Maʾmūn, A.D. 813–33/A.H. 198–213. SUNY Series in Near Eastern Studies. Albany, New York: State University of New York Press.ISBN 978-0-88706-058-8.
• Ibn Taghribirdi, Jamal al-Din Abu al-Mahasin Yusuf (1930).Nujum al-zahira fi muluk Misr wa'l-Qahira, Volume II (in Arabic). Cairo: Dar al-Kutub al-Misriyya.
• Kennedy, Hugh (1998)."Egypt as a province in the Islamic caliphate, 641–868". In Petry, Carl F. (ed.).Cambridge History of Egypt, Volume One: Islamic Egypt, 640–1517. Cambridge: Cambridge University Press. pp. 62–85.ISBN 0-521-47137-0.
• Al-Kindi, Muhammad ibn Yusuf (1912). Guest, Rhuvon (ed.).The Governors and Judges of Egypt (in Arabic). Leyden and London: E. J. Brill.
• Al-Ya'qubi, Ahmad ibn Abu Ya'qub (1883). Houtsma, M. Th. (ed.).Historiae, Vol. 2 (in Arabic). Leiden: E. J. Brill.
• Williams, Caroline (1985). "The Cult of ʿAlid Saints in the Fatimid Monuments of Cairo, Part II: The Mausolea".Muqarnas.3:39–60.doi:10.2307/1523083.JSTOR 1523083.

• 865 deaths
• 9th-century Abbasid governors of Egypt
• 9th-century Arab people

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