Treaty of Orvieto

The Treaty of Orvieto was an agreement made in 1281 between Charles I of Sicily, Giovanni Dandolo, Doge of Venice, and Philip of Courtenay, titular Latin Emperor, for recovery of the Latin Empire, with the blessing of the Papacy. Intended to restore Latin domination, both civil and ecclesiastical, to Greece, it was forestalled by the War of the Sicilian Vespers, which diverted the resources of Charles to the recovery of Sicily.

Charles had long aspired to assemble a trans-Mediterranean kingdom. A younger brother of the French king, Louis IX, he had enlarged his appanage of Provence by agreeing to act as the Papal champion against the Hohenstaufen in 1263. He was rewarded with the Kingdom of Sicily as a papal fief, and almost immediately began to look eastward for further lands. With the defeat of Manfred of Sicily in 1266, Charles sent an army to Albania to seize the dowry of Manfred's wife, Helena of Epirus.

This brought Charles into conflict with Emperor Michael VIII in the Adriatic theater. Baldwin II of Courtenay, then titular Latin Emperor, made a natural ally. Driven out of Constantinople by Michael VIII in 1261, Baldwin was practically penniless and desperate for aid to regain his empire. Charles agreed, but at a significant price: the two signed the Treaty of Viterbo in 1267, wherein Charles agreed to help reconquer the Latin Empire in exchange for the suzerainty of Achaea and other important concessions.

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