War of Saint Sabas

Also known as Saint Sabas war

A property dispute between Venice and Genoa in Acre that escalated into a kingdom-wide civil war pulling in nearly every major faction and permanently weakening the realm's defences.

What began as a property dispute over the monastery of Saint Sabas in Acre between the Italian maritime republics of Venice and Genoa escalated into a full-scale civil war that involved nearly every major faction in the kingdom. The two communes had long competed for warehouses, churches, and tax exemptions inside the city; control of the Saint Sabas estate was the trigger, but the underlying contest was over the commercial primacy of the Latin East.

The factions of the kingdom split sharply along Venetian and Genoese lines. Venice was supported by the Knights Templar, the Count of Jaffa, the Provençal commune of Marseille, and the Ibelins. Genoa was supported by the Hospitallers, the Catalan merchants, the bourgeoisie of Tyre, and Philip of Montfort. Pitched battles were fought in Acre's harbour and streets, and naval engagements ranged across the eastern Mediterranean.

The war devastated the commercial infrastructure of Acre — the kingdom's de-facto capital — and drove the Genoese commune out of the city for the next thirty years. Venice eventually won the naval battles, but the internal division had permanently weakened the realm's ability to coordinate its defences. When Baybars's Mamluks began their methodical reduction of the Frankish strongholds in the 1260s and 1270s, the kingdom met them as a fractured coalition rather than a single state.

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