What are some affects of the crusades had on Europe?

Effects of the Crusades on Commerce

One of the most important effects of the crusades was on commerce. They created a constant demand for the transportation of men and supplies, encouraged ship-building, and extended the market for eastern wares in Europe. Effects of the Crusades on Feudalism

The crusades could not fail to affect in many ways the life of Western Europe. For instance, they helped to undermine feudalism. Private warfare, which was rife during the Middle Ages, also tended to die out with the departure for the Holy Land of so many turbulent feudal lords. Their decline in both numbers and influence, and the corresponding growth of the royal authority, may best be traced in the changes that came about in France, the original home of the crusading movement.