Although the crusades failed to capture Jerusalem, they had several major impacts on Western Europe.
They increased the authority of the king: Sometimes nobles died in battle without leaving an heir in which case the king got their land. Kings passed taxes to pay for the crusades. To pay this tax some nobles had to sell some of their land. Other nobles used the sale of land to offer serfs a chance to buy their freedom. Without as much land, nobles did not need as many serfs. As for the peasants, they were free to leave. They simply never had a reason to do so before. Many young men joined the crusades for adventure. If a peasant died, while serving in the crusades, the king got their land as well. With all this influx of land and money paid to them, the Kings grew to have great power.
Europeans learned many new things from the Muslims including different ways to build and sail ships and how to make and use magnetic compasses. Europeans were also introduced to many new trade goods while on crusade, including silk, cotton, different spices, and new forms of art and literature. The impact on Europe was tremendous. It increased the desire for trade with other parts of the world. This lead to the rise of the merchant class and the end of serfdom.