by cliffelam

Probably in no particular order and overly Euro-centric - would love to hear from people with a different point of view....

I'll start: 1> Communism - Soviet Style 2> Communism - Chinese Style 3> Socialism - German Style (national socialism if you like) 4> WWI 5> Japanese fascism - 1937 onwards 6> Black plague 7> Fall of the Roman Empire 8> Chicxulub Impact (Dinosaur and almost homonid killer) 9> Spanish Conquest of The New World 10> European Colonialism in Africa

Note that I separated the movements that came together to cause WWII because each, on their own, was far more destructive than the war itself.