Foggia Puglia Italy

Aided by Saracen allies, Mandfred defeats the papal army at Foggia on December 2, 1254; he soon establishes his authority over Sicily and the Sicilian possessions on the mainland.

The deposed emperor Baldwin II of Courtenay, who, having fled Constantinople through Greece to Italy and France, is especially active at this time.

He persuades Charles d'Anjou, king of Naples and Sicily, to pension him and sign a treaty for the reconquest of the empire.

Under the Treaty of Viterbo signed on May 27, 1267, Baldwin gifts the Principality of Achaea to Charles

The brother of the French king Louis IX, Charles is the West's ablest diplomat.

Charles in 1266 had advanced into southern Italy at papal invitation expelled the last representatives of the imperial House of Hohenstaufen, Manfred and Conradin, and inherited their titles.

Having at once fixed his gaze across the Balkans onto Constantinople, he, in the words of one chronicler, “aspired to the monarchy of the world, hoping thereby to recreate the great empire of Julius Caesar by joining East and West.”

He begins organizing a coalition of all parties interested in reestablishing the Latin empire, posing as the pope's champion to lead a crusade against the schismatic Greeks.

Baldwin II of Constantinople had been forced to mortgage his young son, Philip of Courtenay, to Venetian merchants to raise money for the support of his empire, which was lost to the Empire of Nicaea in 1261.

By the Treaty of Viterbo in 1267, his father had agreed to marry him to Beatrice of Sicily, daughter of Charles I of Sicily and Beatrice of Provence.

Her maternal grandparents are Ramon Berenguer IV, Count of Provence and Beatrice of Savoy.

The marriage is performed in October 1273 at Foggia; shortly thereafter, Baldwin dies, and Philip inherits his claims on Constantinople.

Although Philip is recognized as emperor by the Latin possessions in Greece, much of the actual authority will devolve on the Angevin kings of Naples and Sicily.