- The Crusades: A series of religious warsfought by European Christians against Muslims, Jews, and other religious groups in the Middle East. It claimed the lives of millions and resulted in the deaths, displacement and conversions of people
- The Spanish Inquisition: A Catholic Church tribunal that tortured, imprisoned and executed thousands of people suspected of heresy.
- The Holocaust: The systematic genocide of European Jews by the Nazis, a Christian regime, which claimed the lives of six million Jews.
- The Rwandan Genocide: A systematic campaign of violence carried out by Hutu Christian extremists against Tutsi Christians and moderate Hutus, resulting in the deaths of up to 800,000 people.
- The Thirty Years' War: A primarily Christian conflict that ravaged Europe from 1618 to 1648, resulting in the deaths of millions of people, mostly civilians, and the widespread devastation of entire regions.