In the late eighth century of the Common Era (the second Islamic century), while Europe was plunged in what we now call the Dark Ages, Baghdad was the centre of one of the most extraordinary civilisations the world has ever seen.

The Prophet Muhammad had been driven from his home town of Makkah (Mecca) for preaching his new doctrine, and when he returned, he came as a conqueror. Military expansion became the norm for Islam, and the Muslim armies were wildly successful. Within a century of Muhammad’s death, the Khalifah (Caliph), the Successor to the Prophet, ruled over an empire that stretched from Tibet to the Atlantic Ocean.

This empire reached its zenith during the reign of Harun al-Rashid. Harun’s grandfather, al-Mansur the Victorious, had come to power as the result of a revolution, and decided to found a new capital free from the taint of the previous regime. Rather than locate it near the holy cities of Makkah, Madinah and Jerusalem, he built his metropolis in the Black Lands of Mesopotamia, the cradle of civilisation. He called it the City of Peace, but it soon became known by the old Persian name for the area: Baghdad.

In less than thirty years Baghdad grew to become the greatest city on earth, with a population estimated to be around one million. The ruling class may have been Arab, but the Persian empire had existed in one form or another for over a thousand years, and the newcomers soon came under its influence. The Khalifate under the Abbasids (the family of al-Mansur and Harun) was culturally diverse, religiously tolerant and intellectually voracious. The foundations of modern science and mathematics were laid here. Scholars preserved, translated and studied ancient Greek and Roman texts, and without their work the European renaissance could not have taken place. Poetry and philosophy flourished.

Like many empires, the Abbasid Khalifate experienced a brief Golden Age followed by a long, slow decline. The death of Harun al-Rashid triggered a civil war from which it never truly recovered, although it survived in name at least for another four hundred years. However, the transmutation of history into legend had begun. In the dark days that followed, people began to tell stories about the young, handsome Khalifah, his loyal Wazir (minister) Ja’far, and his favourite poet, Abu Nuwas, the Father of Locks…