The city of Baghdad was founded in the 8th century as the capital of the Abbasid Caliphate, by its caliph al-Mansur. The Caliphate had just defeated the Umayyads, and al-Mansur wanted his own capital to rule from. He chose a site about 30 km to the north of the Sassanid capital of Ctesiphon, along the banks of the Tigris, and began to draw up plans for its design and construction.

Mansur wanted Baghdad to be the perfect city, to be the capital of the Islamic empire under the Abbasids. To that end, he brought in thousands of architects, engineers, surveyors, carpenters, blacksmiths and over a hundred thousand laborers from across the Abbasid empire. He consulted astrologers, and according to their advice, laid the first ceremonial brick on 30 July 762.

The round city of Baghdad in the 10th century, the peak of the Abbasid Caliphate. Illustration: Jean Soutif/Science Photo Library