Although they were a miserable failure in terms of their planned goals, the Crusades were one of the most important European wars. Before the Crusades, Europe was a desolate place stricken with immense poverty and internal warfare. Feudal lords engaged in skirmishes against each other over petty differences that usually resulted in nothing more than the destruction of much needed farmland and the deaths of much needed laborers. The church tried various methods to curb this violence (the most amusing being what was called "God's Truce," in which it tried to restrict fighting to only certain days of the week), but it was ultimately unsuccessful. The Crusades, however, were able to redirect this violence towards a common enemy. Therefore, feudal warfare in Europe vastly diminished.

Islamic culture had always been more advanced than European, philosophically, intelectually, and technologically. The Crusades helped introduced this advanced culture to Europe, causing an explosion in intellectual and philosophical thought as well as technological developments. As Europeans slowly gained more wealth due to better agricultural conditions and less internal struggles, Europeans began to crave Islamic commodities, such as spice and silk, jump-starting the commercial revolution that hit Europe during the Middle Ages.

Before the Crusades, Europe was considered a wasteland by virtually the entire world. The Muslims considered Europeans to be barbarians, and both they and the Vikings used them simply as a source of slaves and supplies which they took by force. Europe changed dramatically and quickly after the Crusades, and without them, it is quite possible that the Renaissance may never have occurred or occurred much later than it did.

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LET ME SEE YOUR WAR FACE!!!