The Sunni-Shia divide summed up in one map

Sectarian conflict is becoming entrenched in a growing number of Muslim countries and is threatening to fracture Iraq and Syria. Tensions between Sunnis and Shias could reshape the future Middle East.

Iraqis living in Iran hold posters of Shiite Muslim spiritual leader Grand Ayatollah Ali al-Sistani and the Iranian supreme leader Ayatollah Ali Khamenei in southern Tehran on June 20, 2014, against the offensive by Sunni Arab jihadists in Iraq. (Getty)