The rise of Islamic State in Iraq and Syria (ISIS), the Islamist militant group that has seized a chunk of land stretching from northern Syria to central Iraq, has struck fear into the hearts of leaders around the world. CNN explains ISIS’ roots, what it controls, and where its support comes from. The group began in 2004 as al Qaeda in Iraq, before rebranding as ISIS two years later. It was an ally of — and had similarities with — Osama bin Laden’s al Qaeda: both were radical anti-Western militant groups devoted to establishing an independent Islamic state in the region. But ISIS — unlike al Qaeda, which disowned the group in early 2014 — has proven to be more brutal and more effective at controlling territory it has seized. ISIS is putting governing structures in place to rule the territories the group conquers once the dust settles on the battlefield. From the cabinet and the governors to the financial and legislative bodies, ISIS’ bureaucratic hierarchy looks a lot like those of some of the Western countries whose values it rejects.