In 2013 Isis leader Abu Bakr al Baghdadi, 43, declared a merger with the Nusra Front in Syria, then the main al Qaeda affiliate battling President Bashar al Assad.
He did so without consulting either its leader, Abu Mohammed al Golani, or global al Qaeda chief Ayman al Zawahri. He then turned his guns on Nusra, slaughtering Nusra prisoners and posting videos of the decapitations online as a deterrent and recruiting tool.
Isis now includes thousands of foreign fighters and has become the main recruiting magnet for jihadi volunteers from Europe and North Africa and is fast eclipsing al Qaeda as the bête noire of international politics.
Isis now has many attributes of a state. It has taken control of nearly a third of Iraq and much of Syria, has an estimated 10,000 fighters and has assets of about $2 billion (£1.2 billion).
Baghdadi — not his birth name — uses aliases and is said to wear a bandana around his face. To his followers he represents a new generation of fighters working to fulfil the next stage of bin Laden's dream, moving from al Qaeda - which can mean the base in Arabic - towards the fully fledged radical nation.