Holy war

A religious war or holy war (Latin: bellum sacrum) is a war primarily caused or justified by differences in religion. The account of the conquest of Canaan by the Israelites in the Book of Joshua, the Muslim conquests of the 7th and 8th centuries, and the Christian Crusades (11th to 13th centuries) and Wars of Religion (16th and 17th centuries) are sometimes classified as examples. A religious aspect has been part of warfare in some cultures as early as the battles of the Mesopotamian city-states.

However, in the modern period, debates are common over the extent to which religious, economic, or ethnic aspects of a conflict predominate in a given war. Some argue that since the very concept of "religion" is a modern invention, the term "religious war" does not apply to most wars in history. In several ongoing conflicts including the Israeli-Palestinian conflict, the Syrian civil war, and the wars in Afghanistan and Iraq, religious arguments are overtly present but variously described as fundamentalism or religious extremism depending upon the observer's sympathies.

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