The Islamic Caliphates

Around AD 600, two great empires faced each other across the Middle East: the eastern Roman Empire and Sasanian Persia.

From 602 to 628 they fought a long, exhausting war. To their south lay Arabia, a land of trading towns, oases and nomadic tribes that neither empire ruled.

According to Muslim tradition, around 610 Muhammad, a merchant of Mecca, began receiving the revelations that became the Quran.

Facing hostility in Mecca, he and his followers moved to Medina in 622, the Hijra. That year is year one of the Islamic calendar.

By his death in 632, most of Arabia had joined the new Muslim community, the umma, under one leadership for the first time.

The Prophet’s successors were called caliphs. Under the first four, Abu Bakr, Umar, Uthman and Ali, Arab armies took Syria and Egypt from the Romans and destroyed the Sasanian Empire by 651.

Many conquered Christians, Jews and Zoroastrians kept their faith as protected communities who paid a special tax. Conversion to Islam was gradual, over centuries.

A dispute over who should lead turned into civil war after 656. It is the root of the division between Sunni and Shia Muslims: Shia Muslims hold that Ali should have led from the start.

In 661 Muawiya, governor of Syria, became caliph and made Damascus his capital. Leadership now passed within his family, the Umayyads.

The caliph Abd al-Malik made Arabic the language of government and minted new gold coins with words instead of images.

In Jerusalem he built the Dome of the Rock, completed around 691, one of the oldest surviving Islamic monuments.

In 711 Umayyad forces crossed from North Africa into Spain. In the same years, armies reached Sindh on the Indus, and Samarkand in Central Asia.

In 732 a raid deep into France was stopped near Tours and Poitiers by the Frankish leader Charles Martel.

At its height the Umayyad Caliphate covered around 11 million square kilometres, larger than Rome at its peak.

Many non-Arab Muslims, especially in Persia, resented Umayyad favour for Arabs. A revolt that began in Khorasan, in the east, overthrew the Umayyads in 750.

The new caliphs, the Abbasids, descended from the Prophet’s uncle Abbas. Most of the Umayyad family were killed.

One prince, Abd al-Rahman, escaped to Spain and in 756 set up a separate Umayyad state at Córdoba. The Muslim world would never again be under one ruler.

In 751, at the Talas river in Central Asia, an Abbasid army defeated the forces of Tang China. Legend says captured Chinese papermakers taught their craft in Samarkand, though paper was probably already spreading.

In 762 the caliph al-Mansur founded a new capital on the Tigris: Baghdad, a city built in a perfect circle.

Under Harun al-Rashid, around 800, it may have been the largest city in the world outside China.

Abbasid caliphs and rich patrons paid scholars to translate works of Greek philosophy and medicine, Persian literature and Indian mathematics into Arabic.

Around 820, al-Khwarizmi wrote a book on solving equations. Its title gave us the word “algebra”, and his own name gave us “algorithm”.

Scholars in Baghdad, Cairo and Córdoba advanced astronomy, optics and medicine. Many of their books were later translated into Latin and studied in Europe.

From the 800s, provinces broke away under local dynasties. By the 900s there were three rival caliphs at once.

The Shia Fatimids ruled from Cairo, which they founded in 969. The Umayyad ruler of Córdoba declared himself caliph in 929. The Abbasids kept Baghdad.

In Baghdad, real power passed to soldiers and sultans, first Persian Buyids, then Seljuk Turks from 1055. The caliph remained a religious figurehead.

Arab and Persian merchants sailed the monsoon winds to India and China, and settled in ports along the way.

Islam reached Southeast Asia mostly through trade and teachers, not conquest. The kingdom of Samudera Pasai in Sumatra had a Muslim ruler by the late 1200s.

Over the next centuries Islam spread through the Malay world, including Pattani, Malaysia and Indonesia, today the country with the most Muslims in the world.

In 1258 a Mongol army under Hulagu, grandson of Genghis Khan, besieged Baghdad.

The city fell after two weeks. The last Abbasid caliph in Baghdad was put to death, and a great part of the population was killed. Estimates range from tens of thousands to many more.

Libraries were destroyed. For many Muslims the date marks the end of a golden age.

Surviving Abbasid princes were installed as caliphs in Cairo by the Mamluk sultans, with religious prestige but no real power.

After the Ottomans conquered Egypt in 1517, Ottoman sultans increasingly used the title of caliph themselves.

In 1924 the new Republic of Turkey abolished the caliphate. Since then, no caliphate has been widely recognised by Muslims.

The caliphates’ political unity lasted barely a century. But they spread Arabic as a language of faith, law and science from Morocco to Iraq.

Words like algebra, algorithm, zero, coffee and sugar reached European languages through Arabic.

Next: the Khmer Empire of Angkor, in mainland Southeast Asia.