Which crusade was launched in 1239 by Theobald I of Navarre and known as the Barons' Crusade? The Barons' Crusade. Also called the Crusade of 1239, it brought French, Navarrese, English, and other European nobles to the Holy Land between 1239 and 1241.
Pope Gregory IX called the expedition as the truce secured during Frederick II’s Sixth Crusade approached its expiration. Theobald I of Navarre, also count of Champagne, led the first major host, which reached Acre in September 1239. The campaign included a serious defeat at Gaza, where many crusaders were killed or captured.
Despite that military setback, diplomacy produced substantial gains. Theobald negotiated with rival Ayyubid rulers in Damascus and Egypt, helping the Kingdom of Jerusalem regain Jerusalem, Bethlehem, Nazareth, much of Galilee, and other territories. Richard of Cornwall later led another contingent that helped consolidate some of these arrangements.
The name can cause confusion because the expedition involved separate hosts and is sometimes treated as multiple campaigns. Nevertheless, “Barons' Crusade” is the standard canonical answer, unlike the Sixth, Seventh, or Eighth Crusades.