"If we want to understand the Middle East, if we want to understand why conflicts are happening the way they are, and how these conflicts may be resolved, we cannot take our eyes of the Shiite-Sunni conflict, says Vali R. Nasr, Dean of the School of Advanced International Studies at Johns Hopkins University in a video from the Council on Foreign Relations (CFR).
The video is part of an interactive infoguide produced by CFR, that is an in-depth look at the roots of a divide which is at the heart of many of the violent conflicts currently engulfing the Middle East.
"The Shiite-Sunni divide is a political and religious divide around who was the rightful heir after the passing of the Prophet Muhammad in early Islam. Yes, it's remote history, going back to the seventh century, but for millions of Muslims around the world, it's what defines them- sectarianism," says Ed Husain, adjunct senior fellow for Middle Eastern Studies at CFR, in the overview.
Take a look back at the origins of the schism with this interactive timeline:
To see how this ancient dispute has been playing out in the modern word, this timeline starts with Iran's Islamic revolution and goes up to the present day:
Where are these tensions most prevalent? Take a look at the map to see the countries dominated by sectarian conflict and click on the countries to see more about their demographic makeup.