''The Will of God''  is the literal translation of the Latin phrase ''Deus Lo Volt''; a ubiquitous war cry and a common offered explanation of all the horrors and iniquities unleashed by the First Crusade of 1096 to 1099,  when thousands of Europeans made the dangerous and terrifying journey to the Holy Land and the liberation of Jerusalem. It is the first of two books on the subject.

Gilles is the natural son of the Earl Wulfnoth, executed by William the Conqueror for supposed treachery. Raised in Normandy by Queen Matilda of England, Gilles is a young servant of Robert, Duke of Normandy, when the first call for a Holy War against the infidel and for the liberation of Jerusalem is raised in Christendom. Along with thousands of others inspired by a variety of motives, intense piety mixed with a sense of adventure and the prospects of richness, Gilles becomes a key and respected follower of the Duke of Normandy and travels through France and into Italy to the point of embarkation for Constantinople and the land of the Greeks.

In this epic first phase of a long and gruelling journey, Gilles begins to discover a sense of his own strengths and weaknesses, encounters for the first time the full might and strength of the Norman war machine and achieves his much coveted aim of knighthood, as well as a sense of responsibility to the men that he must now lead into battle.