Answer;
Nationalism convinced the people of Europe that their own nation could take on any military threat. This was a role nationalism played in the outbreak of world War I.
Explanation;
Nationalism reached a fevered pitch in Europe prior to the first World War. As a political tool, it was the belief that European technological, cultural, economic and military superiority was the cause for the subjugation of more backward economies and cultures.
The pan-Slavic nationalism inspired the assassination of Archduke Franz Ferdinand in Sarajevo in June 1914, an event that led directly to the outbreak of World War I.
Answer: the French and Indian war in 1763, relations between the American colonists and the British crown and parliament quickly deteriorated.
Wave of invader swept across Western Europe (Vikings, Franks, Goths, and Huns) trade slowed down to a trickle (people became more isolated) towns became empty, and classic learning just stopped.
