In June 2014, an armed group calling itself the Islamic State in Iraq and the Levant (known as ISIL or ISIS) declared the establishment of a caliphate and proclaimed its leader, Abu Bakr al-Baghdadi, a caliph. This proclamation was rejected by the overwhelming majority of the world’s Muslims.

ISIL had attempted to appropriate a title imbued with religious and political significance – and in doing so had cast a dark shadow over a rich history.

This is the story of the caliph, a title that originated 1,400 years ago and that spanned one of the greatest empires the world has ever known.

The Caliph – Part 1: Foundation

The Caliph – Part 2: Division

The Caliph – Part 3: Decline