The Crusades were a series of
defensive wars against Islamic aggression in the Middle Ages and attempts to recapture the Holy Land from Muslim conquerors in order to allow safe pilgrimage and to protect and maintain the Christian presence there. Jerusalem had been Christian for hundreds of years when Caliph Omar seized it, and following that victory, Muslims warred their way into Egypt, other parts of Africa, Spain, Sicily, and Greece, leaving Christians dead and churches in ruins. They stole lands in the area now known as Turkey, destroying Catholic communities founded by St. Paul himself. They siezed Constantinople -- the "second Rome" -- and threatened the Balkans.
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