Abbasid Caliphate (750-1258): The Golden Age of Baghdad

The Abbasid Caliphate was the second great dynasty of the Islamic caliphate, ruling from 750 until the Mongol sack of Baghdad in 1258. Descended from al-Abbas, an uncle of the Prophet Muhammad, the Abbasids overthrew the Umayyads in a revolution that began in eastern Iran, then moved the centre of the Islamic world from Syria to Iraq. Their capital, Baghdad, became one of the largest and richest cities on earth and the heart of a remarkable age of science, scholarship and literature, even as the caliphs’ political power steadily faded.

The Abbasid revolution

By the 740s the Umayyad Caliphate, ruling from Damascus, faced growing opposition. Non-Arab converts to Islam, known as mawali, complained of unequal treatment. Many Muslims believed leadership should belong to the family of the Prophet, and the memory of the Battle of Karbala in 680 still fed anger against the dynasty. The Umayyads were also weakened by feuds among Arab tribes and a costly civil war after 744.

The descendants of al-Abbas built a secret movement, calling for rule by “the chosen one from the family of Muhammad” without naming him. In 747 their agent Abu Muslim raised the movement’s black banners near Merv in Khurasan, in north-east Iran. His armies swept west, took Kufa in 749, and there Abu al-Abbas was proclaimed caliph, taking the title al-Saffah.

In January 750 the Abbasid army defeated the last Umayyad caliph, Marwan II, at the Battle of the Great Zab river in northern Iraq. Marwan fled to Egypt, where he was killed in August 750. Most of the Umayyad family was hunted down and massacred, but one prince, Abd al-Rahman, escaped to Spain and founded a rival state there.

Consolidation and the founding of Baghdad

Al-Saffah died in 754 and was succeeded by his brother al-Mansur (r. 754-775), the true founder of the Abbasid state. He eliminated rivals, including Abu Muslim, whom he had executed in 755 because his power in Khurasan seemed dangerous. He built a central administration based on Persian traditions, with a powerful chief minister, the vizier, and a network of officials.

In 762 al-Mansur began building a new capital on the Tigris, officially named Madinat al-Salam, the City of Peace, but known as Baghdad (see the founding of Baghdad). Its core was a Round City with the caliph’s palace and mosque at the centre. Located near the old Persian capital of Ctesiphon, on fertile land and major trade routes, Baghdad grew rapidly into a vast metropolis.

The golden age

Harun al-Rashid and al-Ma’mun

The Abbasid court reached its greatest splendour under al-Mahdi (r. 775-785) and especially Harun al-Rashid (r. 786-809). Harun’s reign, remembered through the later tales of the Thousand and One Nights, saw immense wealth, lavish patronage and diplomatic contacts as far as Charlemagne’s court. Real power for much of it lay with the Barmakids, a family of Persian viziers, until Harun suddenly destroyed them in 803.

After Harun’s death his sons al-Amin and al-Ma’mun fought a destructive civil war (811-813), which ended with the siege of Baghdad and al-Amin’s death. Al-Ma’mun (r. 813-833) was an intellectual caliph who encouraged theology, philosophy and science. He also tried to impose the doctrine that the Quran was created rather than eternal through an inquisition known as the mihna, which lasted until about 848 and was resisted by scholars such as Ahmad ibn Hanbal.

Learning and science

The early Abbasid centuries saw a huge translation movement. Greek works of philosophy, medicine, mathematics and astronomy, as well as Persian and Indian texts, were rendered into Arabic, often via Syriac. Translators such as the Christian physician Hunayn ibn Ishaq produced versions of Galen, Aristotle and many others.

Scholars associated with Baghdad and its libraries, often linked with the House of Wisdom, built on this knowledge. Al-Khwarizmi wrote the treatise from which the word algebra derives and helped spread Hindu-Arabic numerals. Al-Kindi worked to combine Greek philosophy with Islamic thought. Astronomers measured the earth and compiled tables, and physicians such as al-Razi (Rhazes) wrote influential medical works.

The introduction of paper, made in Baghdad from the late 8th century, made books cheaper and helped spread learning. Bookshops, libraries and copyists flourished.

Religion, law and literature

The Abbasid period also shaped Sunni Islam. The great schools of law took form, named after Abu Hanifa, Malik ibn Anas, al-Shafi’i and Ahmad ibn Hanbal. In the 9th century scholars such as al-Bukhari and Muslim compiled the most respected collections of hadith, the reports of the Prophet’s sayings and deeds.

Arabic literature flowered too, from the wine poetry of Abu Nuwas to the essays of al-Jahiz and the histories of al-Tabari.

Trade and economy

The caliphate linked the Mediterranean with the Indian Ocean and Central Asia. Merchants from Basra and Siraf traded with India, South-East Asia and China, while caravans crossed Iran to the steppe. Silver dirhams minted by the Abbasids have been found in large numbers as far away as Scandinavia and Russia.

Fragmentation and decline

Samarra and the Turkish soldiers

The caliph al-Mu’tasim (r. 833-842) built an army of Turkish slave soldiers, called ghilman or mamluks, recruited from Central Asia. Friction with the people of Baghdad led him to found a new capital, Samarra, about 125 kilometres up the Tigris, in 836.

The Turkish commanders soon became kingmakers. In 861 the caliph al-Mutawakkil was murdered, and in the following decade, sometimes called the “Anarchy at Samarra”, several caliphs were deposed or killed. The court returned to Baghdad in 892. Meanwhile the Zanj Rebellion of enslaved labourers in southern Iraq (869-883) devastated the region around Basra.

Breakaway states

From the start, the caliphate did not control all Muslim lands. Al-Andalus became an independent Umayyad emirate in 756. In North Africa the Idrisids (788) and the autonomous Aghlabids (from 800) went their own way. In the east, the Tahirids, Saffarids and Samanids ruled Iran and Central Asia with little more than formal loyalty to Baghdad, and the Tulunids took Egypt in 868.

In 909 the Shia Fatimids proclaimed a rival caliphate in North Africa, and in 929 the Umayyad ruler of Córdoba also took the title of caliph. The Muslim world now had three caliphs.

Buyids and Seljuks

In 945 the Buyids, a Shia dynasty from northern Iran, took Baghdad. The caliphs remained as religious figureheads, while the Buyid emirs held real power. In 1055 the Sunni Seljuk Turks under Tughril Beg replaced the Buyids and took the title of sultan, ruling in the caliph’s name.

As Seljuk power broke up in the 12th century, caliphs such as al-Nasir (r. 1180-1225) recovered real authority in Iraq. This revival was cut short by the Mongols.

The fall of Baghdad and afterwards

In 1258 the Mongol army of Hulagu, grandson of Genghis Khan, besieged Baghdad. The city fell in February, and the last caliph in Baghdad, al-Musta’sim, was executed. Contemporary and later sources speak of a massacre of many tens of thousands, with estimates ranging up to several hundred thousand, though the true figure is unknown (see the Mongol siege of Baghdad).

In 1261 the Mamluk sultan Baybars installed a surviving member of the family as caliph in Cairo. These Cairo caliphs had religious prestige but no political power, and the line ended after the Ottoman conquest of Egypt in 1517.

Myths and facts

• Myth: the Abbasids ruled the whole Muslim world. Al-Andalus never accepted them, and from the 9th century many provinces were run by independent dynasties that offered the caliph little more than his name in the Friday prayer.
• Myth: the golden age was purely Arab or purely Muslim. Many of its leading translators, doctors and officials were Persians, Christians, Jews or Sabians, and the court drew heavily on Persian traditions of government.
• Myth: the Mongols destroyed a flourishing empire. By 1258 the caliphs had controlled little more than Iraq for centuries. The sack of Baghdad was a catastrophe for the city and its libraries, but the political empire had broken up long before.
• Fact: the Thousand and One Nights is fiction. The stories that feature Harun al-Rashid took shape over centuries and portray an idealised Baghdad, not a historical record of his reign.

Key people

• Abu al-Abbas al-Saffah (r. 749/750-754): first Abbasid caliph.
• Abu Muslim (died 755): leader of the revolution in Khurasan.
• al-Mansur (r. 754-775): organiser of the state and founder of Baghdad.
• Harun al-Rashid (r. 786-809): caliph at the height of Abbasid wealth and prestige.
• al-Ma’mun (r. 813-833): patron of science and philosophy, initiator of the mihna.
• al-Musta’sim (r. 1242-1258): last caliph in Baghdad, killed by the Mongols.

Timeline

• 747: Abu Muslim launches the revolution in Khurasan.
• 749: Abu al-Abbas al-Saffah is proclaimed caliph in Kufa.
• 750, January: the Umayyads are defeated at the Great Zab.
• 762: al-Mansur begins building Baghdad.
• 786-809: reign of Harun al-Rashid.
• 811-813: civil war between al-Amin and al-Ma’mun.
• 836: the capital moves to Samarra; it returns to Baghdad in 892.
• 945: the Buyids take control of Baghdad.
• 1055: the Seljuk Turks enter Baghdad.
• 1258, February: the Mongols sack Baghdad and kill al-Musta’sim.

Why it matters

The Abbasids moved the centre of the Islamic world east and created a cosmopolitan civilisation in which Arabs, Persians, Turks, Christians, Jews and others contributed to a shared culture. The knowledge preserved and developed in their lands later passed to Europe through translations from Arabic. Even after losing power, the Abbasid caliphate remained a symbol of Muslim unity for centuries.