Decline of Abbasid Caliphate

With the Buyid dynasty on the wane, a vacuum was created that was eventually filled by the dynasty of Oghuz Turks known as the Seljuqs. By 1055, the Seljuqs had wrested control from the Buyids and Abbasids, and took any remaining temporal power. When the amir and former slave Basasiri took up the Shia Fatimid banner in Baghdad in, the caliph al-Qa'im was unable to defeat him without outside help. Toghril Beg, the Seljuq sultan, restored Baghdad to Sunni rule and took Iraq for his dynasty.

Al-Azhar Mosque, Cairo, Egypt

Once again, the Abbasids were forced to deal with a military power that they could not match, though the Abbasid caliph remained the titular head of the Islamic community. The succeeding Seljuq sultans Alp Arslan and Malikshah, as well as their vizier Nizam al-Mulk, took up residence in Persia, but held power over the Abbasids in Baghdad. When the dynasty began to weaken in the 12th century, the Abbasids gained greater independence once again.

Nizam al-Mulk, vizier of Seljuq

Al-Mustarshid Billah (1092 – 29 August 1135) became the 29th Abbasid Caliph in Baghdad from 1118 to 1135. Al-Mustarshid achieved more independence as a ruler while the Seljuq Sultan Mahmud II was engaged in war in the East. In 1122, al-Mustarshid deposed and imprisoned his vizier Amid al-dawla Jalal al-Din Hasan ibn Ali. Mahmud II then imposed Ahmad ibn Nizam al-Mulk as his vizier. He sent an army to take Wasit but was defeated near Baghdad and imprisoned in his palace (1126).

Modern Day Baghdad

While the Abbasid Caliph al-Mustarshid was the first caliph to build an army capable of meeting a Seljuk army in battle, he was nonetheless defeated in 1135 and assassinated. He was succeeded by his son Al-Rashid. To avenge his father's death, he insulted the Sultan Mas'ud's envoy who came to demand a heavy largess. Mas'ud hastened to the rebellious capital and laid siege to it. Baghdad, resisted the attack; but in the end the caliph, hopeless of success, escaped to Mosul.

Mustansiriya University, Baghdad, Iraq

In 1136, the Abbasid sultan's power restored, a council was held, the caliph Al-Rashid deposed, and his uncle Al-Muqtafi, appointed as the new caliph. He was the first Abbasid Caliph to regain the full military independence of the Caliphate, with the help of his vizier Ibn Hubayra. After nearly 250 years of subjection to foreign dynasties, he successfully defended Baghdad against the Seljuqs in the siege of Baghdad (1157), thus securing Iraq for the Abbasids.

Zumurrud Khatun Tomb, an Abbasid era mosque, Baghdad

The reign of al-Nasir (r. 1180 CE - 1225 CE), 34th Abbasid Caliph brought the caliphate back into power throughout Iraq, based in large part on the Sufi futuwwa organizations that the caliph headed. Al-Mustansir built the Mustansiriya School, in an attempt to eclipse the Seljuq-era Nizamiyya built by Nizam al-Mulk. Besides his occasional conquests, he consistently held Iraq from Tikrit to the Persian Gulf without interruption. 

Bandar Abbas, Iran, Persian Gulf

In 1206, Genghis Khan established a powerful Mongol Empire of central Asia. During the 13th century, this Empire conquered most of the Eurasian land mass, including both China in the east and much of the old Islamic caliphate (as well as Kievan Rus') in the west. Hulagu Khan's destruction of Baghdad in 1258 is traditionally seen as the approximate end of the Golden Age.

Hulagu Khan

In the 1258 siege of Baghdad, Mongols feared that a supernatural disaster would strike if the blood of Al-Musta'sim, a direct descendant of Muhammad's uncle Al-‘Abbas ibn ‘Abd al-Muttalib, and the last reigning Abbasid caliph in Baghdad, was spilled. So, Hulagu had Al-Musta'sim wrapped in a carpet and trampled to death by horses on 20 February 1258. The Caliph's immediate family was also executed, with the lone exceptions of his youngest son who was sent to Mongolia, and a daughter who became a slave in the harem of Hulagu.

Mongol siege of Baghdad, 1258