Researchers
Baghdad
The Abbasid caliph al-Mansur founded Baghdad in 762 CE on the Tigris as a round city — its heart the caliph's palace and mosque. It became the empire's capital and the seat of Islam's golden age: goods came from the earth's ends, and the House of Wisdom translated philosophy, medicine and astronomy out of Greek, Persian and Sanskrit. For five centuries it stayed civilization's hub, where schools, markets and poets competed. Then Hulagu came in 1258, toppled the caliphate and cast the books into the Tigris; yet Baghdad rose again as the great city of the Two Rivers. From its name came a parable — a city built on the geometry of a circle that became the world's mind. Muslims remember Baghdad as great capitals are remembered: civilization is built with knowledge, wealth and rule, destroyed by division and invasion, and reborn through memory.