1. Nationalism
Nationalism = an ideology focusing and defining the people in a nation
It started from Europe, the definition came after the French revolution in the late 18th century, therefore it is usually called a modern ideology
nationalism has become one of the most important political and social influence in history
Nationalism was one of the possible causes of WW I, and especially of WW II
Fascism rose from Nationalism

2. Continuous escalation during the 19th century, subsecuently culminating in the World Wars.
Nationalism plays to the fundament of human nature.