In the year 750 AD, a revolution swept across the Islamic world. The Umayyad Caliphate, which had ruled from Damascus, was overthrown by a descendant of Abbas, the uncle of the Prophet Muhammad. The Abbasids moved the capital eastward to a new city: Baghdad. Built on the Tigris River, Baghdad became the center of the world. Within a century, it was the largest city on Earth outside China — a metropolis of a million people, a place where Persian viziers, Arab scholars, Syrian Christians, Jewish doctors, and Indian mathematicians worked together in the House of Wisdom (Bayt al-Hikma) to translate and advance the knowledge of the Greeks, Persians, and Indians. Algebra was invented here by al-Khwarizmi. Medicine was transformed by al-Razi and Ibn Sina. The tales of the "One Thousand and One Nights" were set in the streets and palaces of Baghdad. The Abbasids presided over a civilization that was, for 500 years, the most advanced on Earth. But the caliphate slowly fragmented. Regional dynasties — the Fatimids in Egypt, the Umayyads in Spain — broke away. The Mongols, under Hulagu Khan, arrived in 1258. They sacked Baghdad, destroyed the House of Wisdom, and rolled the last Abbasid caliph in a carpet and trampled him to death under horses. The Tigris River ran black with ink from the books of the libraries. The Golden Age of Islam was over.
Summary: The Abbasid Caliphate (750-1258) was the third Islamic caliphate, founded by the Abbasid dynasty. It moved the capital to Baghdad in 762. Under Harun al-Rashid (r. 786-809) and al-Ma'mun (r. 813-833), the Abbasids presided over the Golden Age of Islam, patronizing scholars, scientists, translators, and artists. Al-Khwarizmi, al-Razi, al-Kindi, and Ibn Sina flourished. The empire gradually fragmented; by the 10th century, the caliphs were figureheads controlled by Buyid and Seljuk sultans. The Mongol Ilkhanate under Hulagu sacked Baghdad in 1258, killing the last caliph, al-Musta'sim. A remnant of the Abbasid line continued in Cairo under Mamluk "shadow" caliphs until the Ottoman conquest in 1517.
📚 The House of Wisdom
The Bayt al-Hikma was a library, translation institute, and research center. Caliph al-Ma'mun sent emissaries to the Byzantine Empire to collect Greek manuscripts. The works of Aristotle, Plato, Galen, and Ptolemy were translated into Arabic. Al-Khwarizmi invented algebra. Al-Razi wrote the first medical encyclopedia describing smallpox and measles. Ibn al-Haytham (Alhazen) revolutionized optics.
The Sack of Baghdad — February 13, 1258
"The Mongols breached the walls after a 12-day siege. Hulagu entered the city. The killing lasted a week. The canals ran red with blood. The libraries were burned. The books — centuries of learning — were thrown into the Tigris until the water ran black with ink. The Caliph was rolled in a carpet and trampled to death."
📖 The Legacy
The Abbasid legacy is immeasurable: algebra, algorithms, hospitals, universities, and the preservation of Greek philosophy. When Baghdad fell, the torch of knowledge passed — some to Cairo, some to Cordoba, and eventually, through translation, to the universities of medieval Europe. The Abbasid period remains the cultural peak of Islamic civilization.