The execution of Shiite cleric Nimr Baqr al-Nimr by Saudi Arabia has sparked conflicts in the Middle East along sectarian lines. In a number of Sunni-majority states, protesters of the Shiite minority have taken to the streets to protest Nimr’s death. The events are worrying observers of the region because the divide has not been this deep for centuries and the conflicts appear to be escalating.

Sunni Islam has been the dominant school in the Middle East, and up to 90 percent of the 1.6 billion Muslims worldwide are Sunnis. Syria, Pakistan and Saudi Arabia have Sunni majorities while countries including Iran and Iraq are mostly Shiite. A number of key nations in the Middle East - including Yemen and Lebanon - are relatively split.
(Graphic: Nam Kyung-don)