What war had the most casualties?

1. Death Toll: 55 million Cause: WWII Century: 20C 2. Death Toll: 40 million Cause: Mao Zedong (mostly famine) Century: 20C 3. Death Toll: 40 million Cause: Mongol Conquests Century: 13C 4. Death Toll: 36 million Cause: An Lushan Revolt Century: 8C 5. Death Toll: 25 million Cause: Fall of the Ming Dynasty Century: 17C