27 BC to 180 AD for the Western World. However for Europe since 1946 it has been fairly close to perfect peace, sure there was the fear of the cold war, but for the most part Europe has been with out war. (not counting Yugoslavia) However globally we are very close to another set of world wars, this is because as the world moves closer to a type 1 civilization certain regions are highly resistant to the modern secular world we are moving towards. So the next set of world wars will be a war of Religion versus Humanity.