Pisa, one of the major maritime republics of Italy, has economically and militarily dominated the Ligurian Sea from the eleventh century.

Its principal rival, the Republic of Genoa, has in the thirteenth century conquered numerous settlements in Crimea, where the Genoese colony of Caffa had been established.

The alliance with the restored Roman Empire has increased the wealth and power of Genoa and simultaneously decreased Venetian and Pisan commerce.

The Empire had granted most of free trading rights to Genoa.

Pisa had tried to gain control of the commerce and administration of Corsica, in 1282, when Sinucello, the judge of Cinarca, revolted against Genoa and asked for Pisan support.

Part of the Genoese fleet had blockaded Pisan commerce near the River Arno in August 1282.

Both Genoa and Pisa had made war preparations during 1283.

Pisa has gathered soldiers from Tuscany and appointed captains from its noble families.