Written in the early years of the 1290s, this "recovery treatise" offered advice on the strategies to take back the Holy Land, perhaps in response to the call from Pope Nicolas IV after the fall of Acre in 1291. Largely practical in nature, Charles' first suggestion is that a new Crusade would take careful planning, and that an immediate military response would be foolish. The King argued for an attack by a force composed of all of the Military Orders, united under one Christian prince. Charles also encouraged an economic component to the Crusade, insisting that Christian merchants refuse to trade with the enemy and deny them supplies to grant the advantage to the Christian forces.
Andrew Jotischky, Crusading and the Crusader States. Harlow, Pearson, 2004.
Antony Leopold, How to Recover the Holy Land. Burlington, Ashgate, 2006.
Sylvia Schein, Fideles Crucis. Oxford, Clarenden, 1991.