Abu Muhammad Yahya ibn Aktham (Arabic:أبو محمد يحيى بن أكثم, died 857) was a ninth century ArabIslamic jurist. He twice served as thechief judge of theAbbasid Caliphate, from ca. 825 to 833 and 851 to 854.

Yahya was born inMarw inKhurasan and was a member of theBanu Tamim; he himself claimed descent from the judgeAktham ibn Sayfi. He studiedhadith andfiqh inBasra. In 817-8 he was appointed asqadi (judge) of Basra, and he held that position until 825.^[1]

Following his dismissal from Basra, Yahya was selected byal-Ma'mun (r. 813–833) to serve as chief justice (qadi al-qudat). Yahya enjoyed strong relations with the caliph and became an immensely influential member of the administration, with all decisions made by theviziers being reportedly submitted to him for approval first.^[2] In 831 he participated in al-Ma'mun'scampaign against the Byzantines and was put in command of a raiding party which set out fromTyana,^[3] and in the following year he accompanied the caliph toEgypt and briefly acted as judge there.^[4]

By the end of al-Ma'mun's reign, however, Yahya had fallen out of favor, and he decided to return toIraq. Throughout his career he had been forced to defend himself against consistent allegations ofpederasty,^[5] and by the time of al-Ma'mun's death he was also facing accusations of financial mismanagement.^[6] As a supporter ofSunni orthodoxy,^[7] he was also opposed to theMu'tazilite belief that theQur'an had been created, which put him at odds with the caliph's adherence to Mu'tazilism.^[8] Following the accession of al-Ma'mun's brotheral-Mu'tasim (r. 833–842), Yahya lost his position and was replaced with the Mu'taziliteAhmad ibn Abi Du'ad.^[9]

In 851, following the abandonment of Mu'tazilism byal-Mutawakkil (r. 847–861), Yahya was again made chief judge and he moved toSamarra. During his judgeship he appointed a mix ofqadis, selecting both men who had formerly been affiliated with Mu'tazilism, as well as those who appealed to the orthodoxHanbalis. He remained chief judge until July 854, when al-Mutawakkil dismissed him in favor ofJa'far ibn Abd al-Wahid ibn Ja'far al-Hashimi. His money and land were also seized at the time of his dismissal, and he was placed under house arrest.^[10]

In 857 Yahya decided to go on thepilgrimage and intended to take up residence inMecca. Upon learning that al-Mutawakkil had forgiven him, he changed his mind and set out to return toIraq, but he died on the journey in April 857 and was buried inal-Rabadhah.^[11]

He is generally characterised as having been affiliated with theHanafis, and many state this without specifying his teacher inFiqh. However some do state that he learnt fromWaki' ibn al-Jarrah in particular, who would give juridical opinions on the position ofAbu Hanifah, and that he also relatedHadith reports from one of Abu Hanifa's main students,Muhammad al-Shaybani.Ibn Hazm's view is that he was part of anindependent Basran Ra'y tradition that was later subsumed by theHanafi school.Al-Daraqutni further alternatively lists him as aShafi'i but this is doubted by primary sources.^[12]

• Bosworth, C.E. (2002)."Yahya b. Aktham".The Encyclopedia of Islam, New Edition, Volume XI: W–Z. Leiden and New York: BRILL. p. 246.ISBN 90-04-12756-9.
• Hinds, M. (1993)."Mihna".The Encyclopedia of Islam, New Edition, Volume VII: Mif–Naz. Leiden and New York: BRILL. pp. 2–6.ISBN 90-04-09419-9.
• Ibn Khallikan, Shams al-Din Abu al-'Abbas Ahmad ibn Muhammad (1871).Ibn Khallikan's Biographical Dictionary, Vol. IV. Trans. Baron Mac Guckin de Slane. Paris: Oriental Translation Fund of Great Britain and Ireland.
• Al-Kindi, Muhammad ibn Yusuf (1912). Guest, Rhuvon (ed.).The Governors and Judges of Egypt (in Arabic). Leyden and London: E. J. Brill.
• Al-Mas'udi, Ali ibn al-Husain (1873).Les Prairies D'Or, Tome Septieme. Ed. and Trans. Charles Barbier de Meynard andAbel Pavet de Courteille. Paris: Imprimerie Nationale.
• Melchert, Christopher (1997).The Formation of the Sunni Schools of Law, 9th-10th Centuries C.E. Leiden: Brill.ISBN 90-04-10952-8.
• Melchert, Christopher (1996). "Religious Policies of the Caliphs from al-Mutawakkil to al-Muqtadir: AH 232-295/AD 847-908".Islamic Law and Society.3 (3):316–342.doi:10.1163/1568519962599069.JSTOR 3399413.
• Stewart, Devon J. (2004)."Muhammad b. Jarir al-Tabari'sAl-Bayan 'an Usual al-Ahkam and the Genre ofUsul al-Fiqh in Ninth Century Baghdad". In Montgomery, James E. (ed.).'Abbasid Studies: Occasional Papers of the School of 'Abbasid Studies, Cambridge, 6-10 July 2002. Leuven: Peeters.ISBN 90-429-1433-5.
• Al-Tabari, Abu Ja'far Muhammad ibn Jarir (1985–2007). Ehsan Yar-Shater (ed.).The History of Al-Ṭabarī. Vol. 40 vols. Albany, NY: State University of New York Press.
• Tillier, Mathieu. (2009).Les cadis d’Iraq et l’État abbasside (132/750-334/945). Damascus: Institut français du Proche-Orient, 2009.

• 857 deaths
• 9th-century Arab people
• Sunni Muslim scholars of Islam
• Muslim scholars of Islamic jurisprudence
• 9th-century people from the Abbasid Caliphate
• People from Merv
• Banu Tamim
• 9th-century Muslim scholars of Islam
• Chief qadis of the Abbasid Caliphate
• 9th-century jurists

• Articles with short description
• Short description matches Wikidata
• Articles containing Arabic-language text
• CS1 Arabic-language sources (ar)
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