Mihna in the context of "Al-Ma'mun"

Abū ʿAbd Allāh Muḥammad ibn Ismāʿīl ibn Ibrāhīm al-Juʿfī al-Bukhārī (Arabic: أبو عبد الله محمد بن إسماعيل بن إبرهيم الجعفي البخاري; 21 July 810 – 1 September 870) was a 9th-century Muslim muhaddith who is widely regarded as the most important hadith scholar in the history of Sunni Islam. Al-Bukhari's extant works include the hadith collection Sahih al-Bukhari, al-Tarikh al-Kabir, and al-Adab al-Mufrad.

Born in Bukhara in present-day Uzbekistan, Al-Bukhari began learning hadith at a young age. He travelled across the Abbasid Caliphate and learned under several influential contemporary scholars. Bukhari memorized thousands of hadith narrations, compiling the Sahih al-Bukhari in 846. He spent the rest of his life teaching the hadith he had collected. Towards the end of his life, Bukhari faced claims the Quran was created, and was exiled from Nishapur. Subsequently, he moved to Khartank, near Samarkand.

Ahmad ibn Hanbal (Arabic: أحمد ابن حنبل, romanized: Aḥmad ibn Ḥanbal; (164-241 AH; 780 – 855 CE) was an Arab jurist and founder of the Hanbali school who is widely recognized as the scholar who memorized the most Hadiths in Islamic history. One of the most venerated Islamic intellectual figures, ibn Hanbal is notable for his unmatched memorization of over one million prophetic narrations, an unprecedented number that has never been claimed by any other muhaddith. Ibn Hanbal also compiled the largest hadith collection, al-Musnad, which has continued to exercise considerable influence on the field of hadith studies up to the present time, shaping the methodological framework later employed in both Sahih Bukhari and Sahih Muslim. Imam al-Dhahabi described him as “the true Imam, the proof of the religion, the master of hadith, and the leader of the Sunnah”. Imam Ali ibn al-Madini said: “Truly, Allah supported this religion through two men, to whom there is no third: Abu Bakr during the Ridda Wars, and Ahmad ibn Hanbal during the Mihna”.

Having studied jurisprudence and hadith under many teachers during his youth, Ibn Hanbal became famous in his later life for the crucial role he played in the Mihna instituted by the Abbasid caliph al-Ma'mun toward the end of his reign, in which the ruler gave official state support to the Mu'tazili doctrine of the Quran being created, a view that contradicted the orthodox position of the Quran being the eternal, uncreated word of God. Living in poverty throughout his lifetime working as a baker, and suffering physical persecution under the caliphs for his unflinching adherence to the traditional doctrine, Ibn Hanbal's fortitude in this particular event only bolstered his "resounding reputation" in the annals of Sunni history.

Abū Isḥāq Muḥammad ibn Hārūn al-Rashīd (Arabic: أبو إسحاق محمد بن هارون الرشيد; October 796 – 5 January 842), better known by his regnal name al-Muʿtaṣim biʾllāh (المعتصم بالله, lit. 'He who seeks refuge in God'), was the eighth Abbasid caliph, ruling from 833 until his death in 842. When al-Ma'mun died unexpectedly on campaign in August 833, al-Mu'tasim was thus well placed to succeed him, with the support of the powerful chief qādī, Ahmad ibn Abi Duwad, he continued to implement the rationalist Islamic doctrine of Mu'tazilism and implementing miḥna policy.

A younger son of Caliph Harun al-Rashid (r. 786–809), he rose to prominence through his formation of a private army composed predominantly of Turkic slave-soldiers (ghilmān, sing. ghulām). This proved useful to his half-brother, Caliph al-Ma'mun, who employed al-Mu'tasim and his Turkish guard to counterbalance other powerful interest groups in the state, as well as employing them in campaigns against rebels and the Byzantine Empire.

Ja'far ibn Muḥammad ibn Hārūn al-Mutawakkil ʿalā Allāh (Arabic: جعفر بن محمد بن هارون, romanized: Jaʿfar ibn Muḥammad ibn Hārūn); March 822 – 11 December 861, commonly known by his regnal name al-Mutawwakil ala Allah (Arabic: المتوكل على الله, romanized: al-Mutawakkil ʿalā Allāh, lit. 'He who relies on God'), was the tenth Abbasid caliph, ruling from 847 until his assassination in 861. He succeeded his brother, al-Wathiq (r. 842–847), and is known for expanding the empire to its maximum extent. He was deeply religious, and is remembered for discarding the Muʿtazila, ending the Mihna (a period of persecution of Islamic scholars), and releasing Ahmad ibn Hanbal. He is also known for his tough rule, especially with respect to non-Muslim subjects.

He was assassinated on 11 December 861 by the Turkic guard with the support of his son, al-Muntasir, marking the beginning of the period of civil strife known as the "Anarchy at Samarra".