:lamo My, that's pretty arbitrary. Let's just forget about the Crusades and how they are, in fact, highly relevant to today.
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Mi not highly amigo, Coronado....
Why 300 years? Because I'm trying to be somewhat relevant. 300 years is a pretty damn good trend to show fundamental changes in thinking. If you want to go back further, then you start running into problems with ability to read, access to the religious texts, etc.
As for the Crusades, you seem to be forgetting that Palestine/Israel had been governed by the Eastern Roman Empire from roughly 330AD to 670AD or so when the Muslims overran and conquered the ME. At that time, the population was mainly Christian and Jewish. The Crusades were prompted in large part 400 years later because of Muslim interference with Christian pilgrims, something they hadn't done before.
In fact, the whole history of Christian/Muslim conflict has been Christian defense against Muslim aggression. All of North Africa, Spain & France were mainly Christian before the Muslim expansion and conquest. Muslim expansion in Europe was stopped at Tours, France by Charles Martel. The Moors were driven back, but they weren't evicted from Spain for another 600 years (1492).
The Turks finally conquered Constantinople (Istanbul today) in 1453. They expanded into Christian Greece and the Balkans. They kidnapped Christian children in the Balkans to form the Janizzaries. The source of the ethnic conflict in the former Yugoslavia and Albania was the forced conversion of a portion of the population. Vlad the Impaler aka Vlad Dracul aka Dracula, made his bones fighting the Turks in the Carpathian mountains of Romania. The last Turkish assault on Vienna, Austria was in 1699.
Christian Europeans retook Spain. They held parts of Palestine for a number of years (Outremer), and the Balkans were reconquered. The Spanish population remained Christian under Muslim rule and the Muslims were driven out. Muslims in the Balkans and Eastern Europe pretty much stayed, just the rule changed.
So if you want to go back further, you still don't find what you're looking for. The 1600's had the Reformation and the 30years war, which resulted in a peace between Catholics and Protestants.
In closing, I still think 300 years is generous. Do you judge a nation today, and project its politics, etc., based on what it was and did 100, 200 or 300 years ago? No, you don't. Because it isn't relevant now and it isn't a good indicator for predicting the future.
