What were the reasons for the Crusades?

Crusades are military actions of Christians against Muslims. The main reason was the conquest of new territories in the East. The end of the 10th – beginning of the 11th century in France was given out to be poor and hungry. The rulers wanted to expand the borders of states. But this is hiding behind religious necessity: the liberation of Christian relics in Palestine and the conversion of Muslims to the Catholic faith. The Church wanted to expand its influence and power through these campaigns. But many of these campaigns were unsuccessful.