Samir Abd Muhammad al-Khlifawi was the real name of the Iraqi, whose bony features were softened by a white beard. But no one knew him by that name. Even his best-known pseudonym, Haji Bakr, wasn't widely known. But that was precisely part of the plan. The former colonel in the intelligence service of Saddam Hussein's air defense force had been secretly pulling the strings at IS for years. Former members of the group had repeatedly mentioned him as one of its leading figures. Still, it was never clear what exactly his role was.

But when the architect of the Islamic State died, he left something behind that he had intended to keep strictly confidential: the blueprint for this state. It is a folder full of handwritten organizational charts, lists and schedules, which describe how a country can be gradually subjugated. SPIEGEL has gained exclusive access to the 31 pages, some consisting of several pages pasted together. They reveal a multilayered composition and directives for action, some already tested and others newly devised for the anarchical situation in Syria's rebel-held territories. In a sense, the documents are the source code of the most successful terrorist army in recent history.

Until now, much of the information about IS has come from fighters who had defected and data sets from the IS internal administration seized in Baghdad. But none of this offered an explanation for the group's meteoric rise to prominence, before air strikes in the late summer of 2014 put a stop to its triumphal march.