Why did the medieval Church bless the invasion of Duke William of Normandy in Christian England in 1066 and give its blessings for the cultural genocide that took place in Provence? How could a Western Christian army plunder Constantinople to the point of annihilation in 1204? Why did thousands of ordinary men and women, guided by knights and ladies, kings and queens, embark fervently on ships and set sail for the Holy Land in a campaign of destruction against the world of Islam? The people of that time did not call the occupation of Jerusalem in 1099 the First Crusade, nor the heroic encounter between Richard the Lionheart and Saladin, the famous Saladin, the Third Crusade - this word had not yet been invented. But the idea of a war for faith had long been wandering. Why did the crusades begin and what truth lies behind them are just two of the important questions examined in this book.
Many saw the Crusades as a kind of pilgrimage. Many mistakenly believed that this was God's will, and even more participated for the spoils and the celebration of plunder.

The author, examining aspects of history that have remained unexplored until now, sheds light on religious factionalism, proving that the formation of present-day Europe, as well as the relationships that have been formed between the Christian and Muslim worlds up to the present day, are due to the Crusades.