The crusades were a series of holy wars called by popes with the promise of indulgences for those who fought in them and directed against external and internal enemies of Christendom for the recovery of Christian property or in defense of the Church or Christian people. 

crusading was an act of Christian love and piety that compensated for and paid the penalties earned by sin. 

crusades were fought not only in Syria, Palestine, and Egypt, but in Spain, the Baltic (Latvia and Prussia), Italy, Sicily, and southern France.