[1] 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 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".

Al-Mutawakkil was born on 31 March 822 to the Abbasid prince Abu Ishaq Muhammad (the future al-Mu'tasim) and a slave concubine from Khwarazm named Shuja.

According to the account of al-Tabari, on his deathbed al-Ma'mun dictated a letter nominating his brother, rather than al-Abbas, as his successor,[3] and Abu Ishaq was acclaimed as caliph on 9 August, with the laqab of al-Mu'tasim (in full al-Muʿtaṣim bi’llāh, "he who seeks refuge in God").

Al-Wathiq's mother Qaratis accompanied him, intending to make the pilgrimage, but she died in al-Hirah on 4th Dhu al-Qadah (14 August 842) and was buried in Kufah in the Abbasid palace of Dawud ibn Isa.

Ibn al-Zayyat initially proposed al-Wathiq's son Muhammad (the future al-Muhtadi), but due to his youth he was passed over, and instead, the council chose the 26-year-old Ja'far, who became the caliph al-Mutawakkil.

Not only that, but when the dejected prince left, ibn al-Zayyat wrote to the Caliph to complain about his appearance, noting that he was dressed in an effeminate fashion and that his hair was too long.

Ahmad ibn Hanbal, the founder of the Hanbali madhhab, was arrested and tortured throughout the reigns of, respectively, al-Ma'mun (813–833), his brother and al-Mutawakkil's father, al-Mutassim, and his son al-Wathiq.

In A.H. 236 (850), al-Mutawakkil issued a decree requiring all Christians and Jews in his realm, including Jerusalem and Caesarea, to wear a yellow (honey-colored) hood and belt to distinguish them from Muslims.

Al-Mutawakkil decided to diverge away from the religious policies of the previous caliphs, opting instead to put a stop to the controversy over whether the Qur'an was created or uncreated, ultimately bringing an end to the doctrinal regime that had been in place since 833.

Al-Mutawakkil spent the next several years taking hostile steps against the Mu'tazilites, dismissing a number of Ibn Abi Du'ad's qadis from office and ordering an end to debate over the nature of the Qur'an.

[19] In 850 al-Mutawakkil made a decree ordering Dhimmi (Christians and Jews) to wear the zunnar, honey-coloured outer garments and badge-like patches on their on their servants' clothing to distinguish them from Muslims.

Al-Farghanī, who was not a specialist in public works, made a miscalculation and it appeared that the opening of the canal was too deep so that water from the river would only flow at near full flood.

News leaked to the infuriated caliph might have meant the heads of all concerned save for the gracious actions of the engineer, Sind ibn ʻAlī, who vouched for the eventual success of the project, thus risking his own life.

[25] Also during his reign, al-Mutawakkil met the famous Byzantine theologian Cyril the Philosopher, who was sent to tighten the diplomatic relations between the Empire and the Caliphate in a state mission by the Emperor Michael III.

[29] According to an anecdote from Adab al-ghuraba, a book usually attributed to Abu al-Faraj al-Isfahani, she was a Christian and the daughter of a monk at a Syrian monastery in Homs.

On one Mehregan Day, Shajar's gift of twenty gazelles with Chinese saddles, each carrying gold-latticed bags of precious scents, impressed him.

However, a mishap involving a servant resulted in one of her front teeth being broken, which subsequently turned black, diminishing her appeal in al-Mutawakkil's estimation.

[70] Al-Mutawakkil continued to rely on Turkic statesmen and slave soldiers to put down rebellions and lead battles against foreign empires, notably the Byzantines.

[72][73] In late autumn 861, matters came to a head: in October, al-Mutawakkil ordered the estates of the Turkic general Wasif to be confiscated and handed over to al-Fath.

[74][75] They were soon joined, or at least had the tacit approval, of al-Muntasir, who smarted from a succession of humiliations: on 5 December, on the recommendation of al-Fath and Ubayd Allah, he was bypassed in favor of al-Mu'tazz for leading the Friday prayer at the end of Ramadan, while three days later, when al-Mutawakkil was feeling ill and chose al-Muntasir to represent him on the prayer, once again Ubayd Allah intervened and persuaded the Caliph to go in person.

[73][76] According to al-Tabari, a story later circulated that al-Fath and Ubayd Allah were forewarned of the plot by a Turkic woman, but had disregarded it, confident that no one would dare carry it out.

Al-Muntasir, who now assumed the caliphate, initially claimed that al-Fath had murdered his father and that he had been killed after; within a short time, however, the official story changed to al-Mutawakkil choking on his drink.

The famous scholar al-Taymi said: There were three great caliphs: Abu Bakr, who fought the Apostates until they surrendered; Umar ibn Abd al-Aziz, who made good the abuse of Umayyads and al-Mutawakkil, who abolished heretical innovations and publicly proclaimed Sunnah[82]Ali ibn al-Jahm said: The Caliph al-Mutawakkil sent for me and said, "Ali, I dreamed I saw the Prophet.

[85] Although he was suspected of being involved in the plot to kill al-Mutawakkil, he was able to quickly take control of affairs in the capital city of Samarra and receive the oath of allegiance from the leading men of the state.

Included among these were his secretary, Ahmad ibn al-Khasib, who became vizier, and Wasif, a senior Turkic general who had likely been heavily involved in al-Mutawakkil's murder.

When al-Muntasir died, the Turkic officers gathered together and decided to install the dead caliph's cousin al-Musta'in (Son of his brother Muhammad) on the throne.

[88] The new caliph was almost immediately faced with a large riot in Samarra in support of the disenfranchised al-Mu'tazz; the rioters were put down by the military but casualties on both sides were heavy.

[91] Al-Mutawakkil is featured in the prologue of the video game Assassin's Creed Mirage, in which the caliph is serving as a puppet for the Order of the Ancients, a secret society devoted to restoring humanity to servitude.

He initially protects a Precursor relic on their behalf, but when the game's protagonist Basim attempts to steal it, he fights the young thief and his friend Nehal, who stabs the caliph with his own dagger.