The Abbasid Civil War: The War of the Brothers (811-813)

By Adam Ali

The war between the sons of Harun al-Rashid caused irreparable damage to the economic, political, and military structure of the Abbasid caliphate. The struggle for the throne led to the caliphate’s eventual disintegration and the reduction of the Abbasid caliphs’ power and authority.

The early Abbasid period, specifically the reign of Harun al-Rashid (r. 786-809), is often seen as a “Golden” period of Islamic history. The caliphate was powerful and centralized, while scientific, literary, cultural, and artistic advances and innovations were being made. Its capital, Baghdad, was one of the largest and wealthiest cities in the world. For the most part, the caliphate was also united (al-Andalus was lost to the Umayyads shortly after the Abbasid Revolution and the province of Ifriqiya in North Africa was ruled by the Aghlabid dynasty, which acknowledged Abbasid suzerainty) and ruled by strong and capable caliphs. Hugh Kennedy argues that Harun’s reign is viewed in such a positive light because it is often compared to the period of internecine warfare, struggles, and decline that followed it.


In any case, this “Golden Age” would come to an abrupt end with the death of Harun al-Rashid in 809. The caliphate quickly descended into a state of chaos and anarchy in a long eight-year civil war. The Abbasid Civil War (also known as the Fourth Civil War or the Fourth Fitna) was a bloody, violent, and destructive struggle. The conflict can be divided into two phases. The first phase (811-813) was a war of succession between Harun al-Rashid’s two sons, al-Amin (r.809-813) and al-Ma’mun (r. 813-833), in which al-Ma’mun emerged victorious. The second phase (813-819) was more complex. It involved several factions fighting for political and economic primacy in Iraq. This article will discuss the first phase of the Abbasid Civil War.

Harun al-Rashid’s Succession

One can trace the root of the problem that led to the Abbasid Civil War to Harun al-Rashid’s arrangements for his succession. He named three of his sons as his successors: Muhammad al-Amin, Abdallah al-Ma’mun, and Qasim. In 802 Harun performed the pilgrimage (hajj) to Mecca with his sons and it was at Islam’s holiest site that he formalized the succession. His sons all solemnly agreed to abide by their father’s decision regarding the matter and signed documents that outlined the obligations and rights of each of the heirs, all of whom were half-brothers. Al-Amin was the son of Harun’s wife Zubayda, who also happened to be the granddaughter of al-Mansur, the second Abbasid caliph, making him of Abbasid descent on both his maternal and paternal sides. Al-Ma’mun was the son of Marajil, an Iranian concubine. Some sources state that she was the daughter of the Khurasani rebel leader, Ustadhsis, who had rebelled in Badghis region (several scholars reject the idea that she was really al-Ma’mun’s mother). The third son, Qasim, was not present at Mecca and did not play a major role in the struggle that was to ensure after his father’s death. Tabari briefly mentions the provisions made for him and it seems this was a last-minute addition to the succession.


Harun al-Rashid’s succession document clearly outlined the roles and obligations of each of his heirs. Al-Amin was to succeed his father as caliph in Baghdad and rule Iraq and most of the western parts of the caliphate. Upon his death he was to be succeeded as caliph by al-Ma’mun. In the meantime, al-Ma’mun was to rule the eastern parts of the caliphate, primarily Khurasan, autonomously. That meant that the taxes collected in Khurasan were to remain in the province and that al-Amin’s agents were not allowed into Khurasan without al-Ma’mun’s permission. Additionally, al-Mam’mun would have command of the powerful Khurasani army. Qasim was to be the third in line to the throne. He was granted Northern Syria and the Byzantine frontier region where he received similar rights to autonomy to those held by al-Ma’mun in Khurasan.

At first glance, it seems as though Harun al-Rashid was dividing the empire between his sons. It is confusing, to say the least, as it appears that he was setting them up to go to war with one another. Although his true intentions may never be known, it seems that he was striving for the opposite: to avoid civil war. The caliph was aware of the political situation within his empire and the various forces and factions that were operating behind the scenes. He was also aware of the vast size of the caliphate and the difficulty of ruling it effectively from one location. In fact, earlier Abbasids such as al-Saffah, al-Mansur, and al-Mahdi had appointed members of the Abbasid family as governors to the various provinces. Harun probably envisioned the empire being ruled by his family in a similar manner.

Additionally, each of his sons was the favoured candidate of a powerful faction. Al-Amin was the candidate of the Baghdadis and the abna’ (or “sons”), the military elite and descendants of the Khurasani revolutionaries who had marched west and overthrown the Umayyads in 750. The abna’ were settled in Iraq, concentrated mostly in and around Baghdad and at Raqqa in Syria. Al-Ma’mun was the candidate of the powerful Barmakid family and their supporters. The Barmakids were a dynasty of Iranian wazirs/viziers and had controlled the administration of the empire for several generations. They were also the tutors of the princes of the royal household and had a considerable amount of influence on the caliphs. In fact, al-Amin also had a Barmakid tutor, but as he grew older, he started to gravitate towards the abna’.

Map of the Abbasid caliphate by Cattette / Wikimedia Commons

Perhaps one of the reasons for naming al-Ma’mun as one of his heirs was to appease the Barmakids and their supporters. Al-Qasim, similarly, was under the protection of ‘Abd al-Malik ibn Salih, an important magnate and figure at the caliphal court and the spokesman for Syrian interests. Abd al-Malik was also an important military commander who led campaigns against the Byzantines. This made Qasim the candidate of the Syrians. Harun may have also been trying the appease the people of Khurasan. Many Khurasanis felt that their province should have a special status in the caliphate. It was there that the Abbasid movement was born, and it was with the strength of Khurasani arms that the Umayyads were ousted from power.


During al-Mansur’s reign this problem was addressed by having the crown prince, al-Mahdi, act as his father’s viceroy at Rayy, giving Khurasan a local government of sorts. It seems that Harun was trying to replicate this arrangement with al-Ma’mun. In essence, Harun al-Rashid may have been trying to avoid a civil war between the supporters of each of his sons by outlining each faction’s sphere of influence i.e. the abna’ in Iraq and the west and the Barmakids and their followers in Khurasan and the east.

The document signed by al-Amin and al-Ma’mun in Mecca in 802 outlined their rights and obligations. In it, al-Amin agreed to never interfere in Khurasani affairs, take action against his brother’s agents, aid rebels against his brother, or judge the disputes of the Khurasanis. The document also stated that if al-Amin altered or broke any of these conditions, he would no longer be caliph and all oaths of allegiance sworn to him would be void. Al-Ma’mun had to agree to similar terms promising that he would be loyal and obedient to his brother, acknowledge his superior rank, and to never rebel against him. He also promised to provide military aid to al-Amin whenever he requested it. Al-Mamun, like his brother, would be stripped of all wealth, power, and authority if he broke this covenant.

Harun al-Rashid’s Death and Turmoil in Khurasan

At the time of Harun al-Rashid’s death in 809, the situation in Khurasan was tumultuous. In addition to several Kharijite uprisings, a major rebellion broke out led by Rafi‘ ibn Layth, the grandson of Nasr ibn Sayyar, the last Umayyad governor of Khurasan. The problems in this eastern region were so dire that the caliph decided to ride east personally to restore order.


Several changes had taken place in the caliphate in the years between the signing of Harun’s succession and his death. First of all, the Barmakids were eliminated. They were arrested, stripped of their property and wealth, and imprisoned. One of the Barmakids, Ja‘far ibn Yahya al-Barmaki, was executed. The Barmakids fell due to political, economic, and personal reasons. There is no space here to discuss these reasons in detail, but they include the caliph’s desire to exert political independence and end Barmakid dominance in the government and administration, Harun’s resentment of Ja‘far’s sexual relationship with his sister ‘Abbasa, and pressure from the political rivals of the Barmakids at court.

The most relevant reason for the caliph’s action against the Barmakids was the succession issue. Harun may have thought that the Barmakids would seek to alter the succession after his death. They would not have been satisfied with their protégé, al-Ma’mun, confined to Khurasan and would have probably opposed al-Amin’s succession. It is interesting to note that Ja‘far al-Barmaki, the only Barmakid who was executed, was also very close to al-Ma’mun. Similarly, Abd al-Malik ibn Salih, the power broker who had supported Qasim as a candidate for succession, was also arrested and imprisoned on the charge of conspiring to usurp the caliphate.

Harun al-Rashid and the barber from a 15th-century manuscript – British Library Or. 6810, f.27v

Others filled the void left by the Barmakids. Fadl ibn Rabi‘a, a long-time rival of the Barmakids rose to prominence, he was the hajib (chamberlain) and one of the chief officials at the caliphal court. The administration, after the Barmakids’ fall, was dominated by Fadl ibn Rabi‘a and Isma‘il ibn Subayh (who had been the wazir/vizier of al-Hadi, Harun’s brother), and their followers. The loyal general, Harthama ibn A‘yan remained the chief of the guard and Harun’s right-hand man. A protégé of the Barmakids, Fadl ibn Sahl, took over as al-Ma’mun’s tutor and chief advisor and would play a vital role in the civil war.

The situation in Khurasan at the end of Harun al-Rashid’s reign was unstable. Discontent, local uprisings, and a major rebellion prompted the caliph to march east to personally oversee matters in the huge province. Tax revenues and political authority were at the core of the problems. The governors of Khurasan were, for the most part, appointed from among the abna’, the descendants of Khurasanis who had settled in Iraq. Their interests lay in Iraq and, to the chagrin of the inhabitants of Khurasan, they sent the province’s tax revenues back to Baghdad. The abna‘ had always demanded that the revenues of Khurasan be sent west to pay their salaries and pensions. On the other hand, the Khurasani nobles and magnates, the dihqans (landed gentry), and soldiers residing in Khurasan objected to this arrangement and wanted the revenues to remain in their province.


This situation was mitigated while a Barmakid, Fadl ibn Yahya ibn Barmak, was the governor of the province from 793 to 796. During his tenure the taxes were spent on building projects and on the local military, funding expeditions on the eastern frontier of the empire. In 796 Ali ibn ‘Isa ibn Mahan, one of the commanders of the Abna’, was appointed to the governorship of Khurasan. He exploited the resources of the province ruthlessly and pressed the magnates of Khurasan harshly. Harun al-Rashid initially ignored the complaints against his governor partially due to the lavish gifts and large sums of money Ali ibn ‘Isa sent to the caliphal court.

As a result of the caliph’s inaction, Kharijite rebellions broke out across the province and more seriously, a major revolt broke out in Samarqand in 806 led by the aforementioned Rafi‘ ibn Layth, which attracted widespread support among both the soldiers and the dihqans. The caliph could no longer ignore the situation in Khurasan, especially because his governor was unable to restore order. He dismissed Ali ib ‘Isa, had him imprisoned, and replaced him with Harthama ibn A‘yan, his right-hand general and a member of a Khurasani dihqan family. Despite these changes and several military successes on the part of Harthama, the rebellion continued. In 808, Harun set out for Khurasan to personally deal with the uprising. Fadl ibn Sahl was able to convince him to take al-Ma’mun on the expedition, since Khurasan was to be the seat of his power after Harun al-Rashid’s death. The caliph left Qasim in Syria and al-Amin in Baghdad to ensure a smooth transition of power in the event of his death. Harun died during the expedition near the Khurasani city of Tus in 809.

The Road to Civil War

Both al-Amin and al-Ma’mun were in position in Baghdad and Marw (or Merv) to assume their roles as caliph and ruler of Khurasan. Almost immediately, al-Amin began to undermine his brother’s position in his province. He recalled his main supporters who had gone to Khurasan with the Harun al-Rashid. Among these men was Fadl ibn Rabi‘a. The caliph also sought to weaken his brother’s position by depriving him of funds and his army. He sought to have Fadl ibn Rabi‘a take control of the army and his father’s royal treasury. The army was already in Marw under al-Ma’mun’s command, but Fadl was able to seize the treasury and return with it to Baghdad.

Meanwhile, Ali ibn ‘Isa ibn Mahan was released from prison almost immediately after Harun’s death. He and others from among the abna’ and the militant party in Baghdad started to pressure al-Amin to reassert control over Khurasan and its riches. Al-Ma’mun, also faced difficulties. He had to deal with Rafi‘ ibn Layth’s rebellion and although he had a large army, it was composed primarily of abna’ from Baghdad and he did not trust it. Additionally, with the loss of the funds, much of which had been collected from Khurasan, he did not have the financial means to execute an effective campaign.

The two brothers spent two years negotiating via letters. Al-Amin had asked his brother to come to Baghdad to advise him on certain matters, but al-Ma’mun, sensing a trap, replied that he had to stay in Khurasan and defend it from the rebels. Al-Amin then started making demands including the ceding of some of the border regions of Khurasan to him. He also asked for a part of the tax revenues and demanded that one of his agents be allowed in the east to keep the caliph appraised of the situation in the province. Al-Ma’mun almost caved to these demands. However, his camp also contained militant advisors. Chief among them was Fadl ibn Sahl, his wazir/vizier.

Over time, the exchanges between the brothers became more bitter; al-Mamun cut off the barid (postal service) to Iraq, leaving al-Amin poorly informed regarding the situation in the east. On the other hand, al-Ma’mun had a good intelligence network in Iraq. He was aware of the situation in Baghdad and could communicate with the court officials and army leaders there. He also ordered the western border of Khurasan to be shut to all, except for some merchants and his own agents. Additionally, he proclaimed himself “imam,” a title used for the first time by an Abbasid and purposefully ambiguous. In Iraq, al-Amin formally removed both of his brothers from the succession and replaced them with his son. The militants on both sides were gaining ground. Ali ibn ‘Isa urged al-Amin to invade Khurasan. He not only wanted to revenues, but also to return to his old position as the ruler of the province.

The populace pays Allegiance to the Abbasid caliph, Al-Ma’mun in 813. (from the book Tarikh-i Alfi 1593 CE)

Al-Ma’mun needed to prepare for the inevitable clash. If his brother attacked Khurasan he would be stuck fighting a war on two fronts against the rebels to the east and his brother’s forces advancing from the west. Fadl ibn Sahl orchestrated the entire plan for conducting the war. His first move was to make peace with the rebels. After some negotiation, Rafi‘ ibn Layth surrendered to Harthama and was treated with leniency and generosity. This peaceful conclusion to the rebellion led to several of the rebels joining al-Ma’mun’s army.

Fadl ibn Sahl also urged al-Ma’mun to conclude alliances with the magnates and princes of Transoxiana and the frontier lords, many of whom were fighting against the caliphate. This action was not popular among many of the commanders and soldiers of the abna’ who had come with al-Mamun from Baghdad and most of them deserted him. As a result of this development, al-Ma’mun’s main military support came from the dihqans, Rafi‘ ibn Layth’s former rebel army, and the frontier lords and the princes and chieftains of Central Asia. The troops were probably mostly East Iranians, but also included Arabs, Turks, and others.

The War of the Brothers

The hostilities that mark the beginning of the Abbasid Civil War began in 811. Ali ibn ‘Isa led a large army of abna’ in an invasion of Khurasan. The army that marched from Baghdad was reportedly 40,000 strong. Arab tribesmen and mountain brigands joined Ali ibn ‘Isa’s forces as he marched east in the hopes of gaining spoils. The confident Ali ibn ‘Isa even carried silver chains with which to shackle al-Ma’mun to drag him back to Baghdad in shame.

Al-Ma’mun’s situation seemed hopeless. He had sent a small force under the command of an obscure dihqan, Tahir ibn Husayn, to Rayy on the western frontier of Khurasan. Tahir was of Arab origin. His family had moved to Bushang during the Umayyad period and had become the hereditary rulers of the town. By the time Tahir was born they had become fully Iranianized and had formed strong ties with the other dihqan families in the region. Tahir’s force was significantly smaller than the army marching east from Baghdad. The sources report he had 3,800-5,000 men. Rather than take refuge behind the walls of Rayy, Tahir opted to meet the superior force of his enemy in a pitched battle. Some sources even suggest that the people of Rayy, not wanting to get embroiled in the conflict, locked the gates leaving Tahir with little choice.

The Battle of Rayy not only decided the outcome of the civil war, but also had a major impact on the military traditions of the Muslim world and the composition and organization of its armies. The accounts of the battle in the sources are vague and unclear. However, it appears that Ali ibn ‘Isa’s army of abna’ was organized in the traditional manner with a center and right and left wings. It also seems to have been predominantly composed of infantry (typical of the armies of early Islamic warfare). The army was organized into regiments of 1,000, with the armored men in the front ranks, implying that not all the troops wore heavy armor. On the other hand, Tahir’s small army was composed primarily of horsemen, both shock cavalry and mounted archers. They were organized in mobile squadrons. It seems that Tahir concentrated the bulk of his forces in his center and hit the abna’ very hard in the middle of their battle line. Even though Ali’s forces fared better on the flanks, the momentum of the heavy cavalry charge brought Tahir’s main force close to the commander and Ali ibn ‘Isa was killed early in the battle.

With their commander dead, al-Amin’s forces lost heart. Without any other notable officers, the large force was routed. Ali ibn ‘Isa’s son Yahya attempted to rally his father’s retreating troops but failed. The brigands and tribesmen who had joined al-Amin’s forces melted away and returned to their homes in the mountains, while the abna’ retreated to Hamadhan. Tahir ibn Husayn was catapulted overnight from being an almost unknown dihqan to al-Ma’mun’s chief commander. Prior to the battle, he had proclaimed his lord as the caliph, taking the conflict even further to a point of no return. After the victory at Rayy, al-Ma’mun was proclaimed and acknowledged as caliph throughout all of Khurasan and the prayers were said solely in his name.

Tahir did not sit on his laurels after his victory. He took the initiative and set off in pursuit of the defeated enemy army across the Iranian plateau and through the Zagros Mountains. His quick movements did not allow his foe any time for respite or to regroup. His actions were successful, and he did not meet any serious opposition until he reached Hamadhan where Abd al-Rahman ibn Jabala, an officer of the abna’, had ensconced himself with 20,000 soldiers. Abd al-Rahman’s forces left the city on two occasions to fight Tahir but were driven back both times. Tahir then besieged the city for one month.

It was the inhabitants of Hamadhan who, like those of Rayy, resented their city being used as a battleground. They forced Abd al-Rahman to sue for peace. He and his army were taken prisoner by Tahir, who continued his westward march. However, when Tahir’s forces were crossing the steep Asadabad pass, Abd al-Rahman and his men escaped and launched a surprise attack. Tahir’s forces, although taken by surprise, were disciplined and defeated the ambushers, killing many of them including their leader.

Tahir finished crossing the Zagros and settled down for the winter to give his army a much-needed break. He had defeated two large enemy armies and driven out all of al-Amin’s supporters from Khurasan. He understood that he was now in enemy territory with a small army and that he needed reinforcements before he could continue his advance. Furthermore, Iraq’s landscape was different from the plains of the Iranian plateau. Its networks of canals, rivers, palm forests, and wetlands were not conducive to mounted warfare, something that was not lost on a commander such as Tahir.

In Baghdad, Al-Amin received the news of his armies’ defeats with apathy. The sources present him as a poor leader. The caliph had lost his most important supporters. Ali ibn ‘Isa was dead and Fadl ibn Rabi‘a had gone into hiding after his warmongering policies had failed. There was dissension in Baghdad, primarily around the privileged position of the abna’, who had been repeatedly defeated by Tahir.

Al-Amin and his officials attempted to supplement the ranks of their armies by recruiting new soldiers. Soldiers and warriors were not in short supply. There were Arab tribesmen in Iraq and Syria; many of the Syrians were from military families that had served the Umayyads. However, these new troops demanded a share in the privileges and power of the abna’. An army of 20,000 abna’ and 20,000 Arabs was assembled to attack Tahir. The expedition never made contact with the enemy. The Arabs complained about discrimination by the abna’ and demanded a year’s pay and 1,000 horses. When the army finally did start to move, Tahir sent agents to sow dissent and it broke apart.

Another army of Arabs and abna’ was assembled at Raqqa. The abna’ were under the leadership of Husayn, Ali ibn ‘Isa’s son. The Arabs (Qalbites from Hims and Damascus and Qaysites or Zawaqil from Northern Syria) were led by Abd al-Malik ibn Salih, who had been released from prison to rally support for al-Amin. There was bitterness and tension between the Syrians and the abna’ that went back generations to the Battle of the Zab River, which had been the conclusive clash of the Abbasid Revolution in 750. Violence exploded when one side accused the other of stealing a horse. The abna’ won the fight, the Arabs dispersed, and Husayn ibn Ali led his troops back to Baghdad. During this episode, Abd al-Malik died and with him, all hopes of gaining the support of the Syrians against al-Ma’mun’s forces also perished.

Tahir was able to resume his march into Iraq with the arrival of reinforcements. The veteran general Harthama ibn A‘yan arrived on the scene with 30,000 men and took over as the commander of the operation. Tahir marched to Ahwaz, which he captured. The governor of Ahwaz, Muhammad ibn Yazid al-Muhallabi, sought refuge behind the city walls with his army, but he was pursued closely by Tahir’s forces. Al-Muhallabi’s men launched a sortie against their pursuers who beat them back. The governor and his remaining soldiers then hamstrung their horses, committing themselves to fight to the end. They fought fiercely to the last man.

Tahir then moved against Wasit, which fell without a fight. Al-Amin’s governors, agents, and garrisons abandoned their posts as al-Ma’mun’s armies advanced. Kufa and Basra surrendered shortly afterward. Mosul, Egypt, and the Hijaz also declared for al-Ma’mun. By April 812 it was only Baghdad, Syria, and Ifriqiya that had not acknowledged al-Ma’mun as the new ruler. Syria was in a state of chaos and Ifriqiya was too far away to play a role in the outcome of the conflict.

The Battle for Baghdad

To make matters worse for al-Amin, there were rifts among his supporters in Baghdad. The abna’ were divided into two factions, those who resided on the west bank of the Tigris in the Harbiyya quarter and those living on the east bank of the Tigris in the Rusafa suburb. Ali ibn ‘Isa’s family had drawn its support from those living on the east bank. Husayn ibn Ali, after returning to Baghdad from Raqqa, realized that his best course of action was to surrender Baghdad to al-Ma’mun to avoid any further losses in men, material, and prestige. The abna’ of the west bank were reluctant to support him and rallied around their own leader, Muhammad ibn Abi Khalid, a member of a prominent family that had supported the Abbasids in their rise during the revolution. The West Bankers now formed their own faction and refused to cooperate with Husayn and his East Bankers.

The caliph summoned Husayn in the middle of the night. The abna’ leader refused the summons and mustered his followers the following morning. They marched to the caliph’s palace, defeating a group of Arabs sent by al-Amin to stop them. There was a coup taking place in the palace simultaneously. When Husayn arrived, he and his men renounced their allegiance to al-Amin, justifying their actions by saying he had betrayed them to the Zawaqil and the other Arabs he had attempted to recruit. The West Bankers, however, were not convinced and came to the caliph’s rescue. Led by Muhammad ibn Abi Khalid, they defeated the East Bankers in a series of street battles and rescued the caliph. Husayn was killed as he attempted to flee to join Harthama’s army. The victorious west Bankers renewed their oath of allegiance to the caliph. The events of this “mini civil war” inside Baghdad among the abna’ factions took place in less than a week.

Al-Amin, despite being given a second chance, failed to unify his supporters. His mistrust of his army grew deeper and rather than reward his loyal West Bank abna’, he distributed arms and money to the common people hoping to use them to defend Baghdad against al-Ma’mun’s encroaching armies and to protect him from future coups and mutinies by the regular soldiers of his army. On the other hand, the abna’ of the Harbiyya quarter who had rescued him received nothing. Predictably, these regulars deserted and joined Tahir’s advancing army.

Map of Abbasid Baghdad – image by William Muir (1819–1905)

Al-Ma’mun’s forces besieged Baghdad in August 812. The siege would continue for 13 months with periods of intense fighting. Three armies encircled the Abbasid capital. Harthama ibn A‘yan and his army besieged part of the city on the east bank of the Tigris. Tahir’s army, enlarged by the abna’ of the Harbiyya quarter attacked from the west and the north. A third general, Zuhayr ibn al-Mus‘ab, attacked from the southeast. This last army was the smallest but had a large number of siege engines that wrought devastating destruction on the city. By the time the siege commenced the majority of the defenders were composed of the commoners whom the caliph had armed and paid. The sources refer to these soldiers in a derogatory and contemptuous manner calling them ayyarun, meaning vagabonds or vagrants, and describe them as a mob, scum, and plebs and even state that some of them were escaped criminals (or perhaps criminals released from prison to fight for the caliph). They are also called the “naked ones” because most of them did not wear armour leaving them exposed in combat with Harthama and Tahir’s heavily armoured soldiers.

There was heavy fighting throughout the siege. The round city was walled, but the suburbs around it were not. Most of the fighting took place in the streets and alleys and from house to house. The battles were hard-fought and bloody. Every street, alley, and house was contested and sometimes the same house exchanged hands multiple times as the tide of battle swung one way and then the other. The civilian defenders of Baghdad threw up makeshift fortifications and barricades and used siege engines of their own to slow down the attackers’ advances. Despite the defenders’ inferior armour and weapons and their lack of discipline and military experience, they put up a hard fight. They threw back several assaults by Tahir and Harthama in the western and eastern suburbs of the city.

In February 813, Tahir launched a major attack aiming to cut communications between the east and the west banks. After a fierce fight, the attackers were driven back. Harthama fared even worse, his troops were driven entirely out of the eastern suburbs. In the confusion of the rout, the ayyarun captured Harthama but did not recognize him. The fortunate general was released, but not before his captors cut off his hand. It was Tahir’s quick actions that saved the situation. He constructed a makeshift bridge and sent some of his troops to restore the situation on the East Bank. The fighting continued for months, and the defenders stubbornly refused to surrender. They were fighting for Baghdad and for a newly elevated place for themselves in their city and society.

It was only in September 813, more than a year into the siege, that the attackers were able to gain the upper hand. Tahir managed to convince some of the wealthy citizens and merchants to defect. The upper class of Baghdad had looked upon the rise of the ayyarun in distaste and fear. The rabble had often raided the homes of the wealthy when they were low on money and supplies. The defection of these wealthy Baghdadis was the key to Tahir’s victory. They cut the bridges linking the east and west banks of the city and severed the communication between the two sides. Isolated and cut off from reinforcements and supplies, East Baghdad surrendered after the destruction of the bridges without much fighting. The remaining defenders were then driven back to the round city. It was only a matter of time before the siege was over.

Al-Amin was once again in a very precarious position. Some of his advisers urged him to flee the city with a guard mounted on the remaining horses. They advised him to ride to Syria and gather an army there. Tahir got wind of these plans and coerced some of al-Amin’s wealthier advisers to convince him to remain in the city by threatening to confiscate their lands and wealth when the siege reached its inevitable conclusion.

Once again, al-Amin made the wrong choice, he opted to remain in the city and to surrender. He chose to surrender to Harthama ibn A‘yan an old and loyal servant of the Abbasid family, knowing that no harm would come to him as his prisoner. Even though he was included in the negotiations, Tahir was suspicious of the arrangements made for the caliph’s surrender. He was to receive the symbols of caliphal office the staff, ring, and mantle of the prophet, while Harthama was to take al-Amin into custody.  Tahir believed he would be sidelined and excluded from the rewards he believed that he had rightfully earned for his service in the war. He was also concerned about what might happen if Harthama were able to reconcile the two brothers.

On September 25 813, Harthama arrived on the west bank of the Tigris in a small boat and was met by al-Amin, whom he greeted respectfully. When the boat set out for the east shore to return to Harthama’s camp, it was attacked and sunk by Tahir’s men who lay in ambush along the shorelines. Both Harthama and the caliph were able to survive and swam to shore. Al-Amin was now all alone. He was captured and imprisoned in a house on the west bank. A few hours later a group of Tahir’s Iranian soldiers entered the house and killed the Caliph. Al-Amin’s final moments were witnessed by another prisoner, Ahmad ibn Sallam, a former official in al-Amin’s judiciary. He was released from captivity after paying a ransom and he gives a vivid description of al-Amin’s final moments; how the half-naked caliph desperately fought for his life against the armed men with nothing but a pillow. He almost managed to wrest a sword from the hand of one of his assailants before he was overwhelmed and slaughtered. His severed head was taken to Tahir, who sent it to al-Ma’mun along with the staff, ring, and mantle of the prophet.

With al-Amin’s death and the fall of Baghdad it seemed as though the civil war was over. Al-Amin was dead, and al-Ma’mun was proclaimed caliph in Marw. The fighting in Iran and Iraq had taken its toll in lives and damage. The Abbasid army was fractured and a shadow of what it had been. It needed to be rebuilt and reorganized. Baghdad was in ruins, its wealth plundered and its population decimated. The economy was also impacted by the war and revenues were at their lowest in years. Syria was in a state of chaos and the Khurramiyya were in open rebellion in the Jibal region and in Azerbaijan.

Al-Amin’s murder also damaged the prestige of the Abbasids. He was the first caliph to be killed, an act that cancelled the notion of the inviolability of the caliph. If al-Amin could be ignominiously deposed and killed, so could other Abbasid caliphs; his death foreshadowed future depositions and murders of Abbasid rulers.

However, all was not as it seemed. The tensions continued to simmer in Iraq and Khurasan. Al-Ma’mun, under the influence of his vizier, Fadl ibn Sahl, was convinced to remain in Marw and to rule the empire from Khurasan. This news was not received well in Baghdad. To add insult to injury, Fadl’s brother, Hasan ibn Sahl, was sent to Baghdad as its governor. He had neither the political power nor the military support to successfully enforce his rule there. Disillusioned with the policies of the vizier, Tahir withdrew to Raqqa to bide his time and Harthama journeyed back to Khurasan to inform the caliph of the volatile situation in his realm and to warn him of the ambitions of the power-hungry Sahlids.

The decision of al-Ma’mun to remain in Khurasan and to delegate his power to his vizier would result in six more years of fighting in Iraq, the events of the years 813-816 will be discussed in my next article.

Adam Ali is a lecturer at the University of Toronto. Click here to read more from Adam.

Top Image: A dish from Iran, 9th–10th century – image courtesy Metropolitan Museum of Art