Today an agreement almost ended a crusade.
The fighting had gone on for almost 200 years. The First Crusade was prompted in 1095 by Muslim advances into the lands of the Byzantine Empire, though Pope Urban II quickly saw a religious war to “free” the Holy Land as a way to redirect European knighthood away from the destructive pursuit of deadly tournaments, as well as giving them the promise of new wealth and power (vs. them having to kill one another to get it). The fight would be easy, Urban told cheering crowds, and Deux vult (God wills it). Thousands applied and, over the course of the next two centuries, conducted nearly incessant warfare, swapping lands and spilling blood in battles with sultans and other proponents of a Muslim caliphate (both sides were happy to slaughter any Jews they encountered along the way).
When some crusader castles came under attack in 1267 and France’s King Louis IX called for an Eighth Crusade, however, enthusiasm for another trek across the sands of the Middle East met with a muted response. His scheme was reduced to an attack on the city of Tunis, for which his forces landed on the African coast in July. Many of his soldiers soon became sick from drinking polluted water and other diseases common to the dead of summer. Louis himself was dead from “flux in the stomach” by August, and his brother Charles took nominal control of the nominally-fit forces. He prompted negotiated a truce with the sultan in Tunis on this day that guaranteed free passage of his troops home and free trade with Tunis thereafter. England’s Prince Edward, who’d arrived too late to get a piece of the fighting, began the long trip home, which by some historians constituted a Ninth (and last) Crusade since he stopped to help defend one of the Christian castles that had prompted the trip in the first place. His dad died before he returned to England, which meant he was anointed King Edward I. Frequent fighting with his neighboring Scots (and their Braveheart leader William Wallace) over wealth and power would consume much of his rule.
As for redirecting the idle proclivities of the nobility, the arrival of the Black Death a half-century later would rework European civilization far more extensively than the Crusades had affected the world.