Religion and ethnicity in the Levant

The Islamic State of Iraq and Syria is a result and a driver of sectarianism, not of diversity itself, but to understand how the group works and where it comes from you still have to understand the religious and ethnic composition of the region. You can immediately see two key facts on this map. First, big parts of Syria and Iraq are ethnically Arab and religiously Sunni Muslim, marked in yellow; so is ISIS, and they principally operate in those yellow areas. Second, much of the region is quite diverse: a big chunk of southern Iraq is Shia Muslim and Arab. And there is an ethnically Kurdish minority stretching across both countries, while western Syria is a super-diverse mix of Shia, Christian, Druze, and other groups. Those non-Sunni, non-Arab groups are running the governments of both countries, which is a source of real unhappiness among Sunni Arabs who feel dispossessed. But now ISIS is also brutally oppressing, and in many cases massacring, all other sectarian groups. The fact that national borders don't line up with ethnic and religious lines did not cause ISIS or the larger conflicts, but it has become a major part of the violence.