I strongly recommend this amazing video by “Real Crusades History.” It is worth watching this video as an introduction, and then going through the entire series in your own time. It frames the Crusades in an overall positive light, as a mindset, a unifying epoch which helped to give Europe its identity as Europe, and ultimately ensured its survival.
The Crusades were a counter-attack, an attempt to reclaim territory which had been devoured by the Arabs who swept out of their homeland in the 6th and 7th centuries under the banner of Islam. Although the Crusaders were eventually pushed out of the Middle East, the Crusades were also conducted on European soil to push Islam out of Italy, Spain, and Eastern Europe.
Ultimately, it was the Crusades, and the Crusader mindset, which allowed Europe to survive as an entity – without the Crusades, Europe would now be a part of the Islamic world.
Perhaps they gave Europe another thousand years grace..
