enice's relations with the Byzantine Empire were temporarily disrupted by the Fourth Crusade and its aftermath, Genoa was able to improve its position. Genoa took advantage of this opportunity to expand into the Black Sea and Crimea. Internal feuds between the powerful families, the Grimaldi and Fieschi, the Doria, Spinola, and others caused much disruption, but in general the republic was run much as a business affair. In 1218–1220 Genoa was served by the Guelph podestà Rambertino Buvalelli, who probably introduced Occitan literature to the city, which was soon to boast such troubadours as Jacme Grils, Lanfranc Cigala, and Bonifaci Calvo. Genoa's political zenith came with its victory over the Republic of Pisa at the naval Battle of Meloria in 1284, and with a temporary victory over its rival, Venice, at the naval Battle of Curzola in 1298.
However, this prosperity did not last. The Black Death was imported into Europe in 1347 from the Genoese trading post at Caffa (Theodosia) in Crimea, on the Black Sea. Following the economic and population collapse, Genoa adopted the Venetian model of government, and was presided over by a doge (see Doge of Genoa). The wars with Venice continued, and the War of Chioggia (1378–1381)-- where Genoa almost managed to decisively subdue Venice—ended with Venice's recovery of dominance in the Adriatic. In 1390 Genoa initiated a crusade against the Barbary pirates with help of the French and laid siege to Mahdia. Though it has not been well-studied, the fifteenth century seems to have been a tumultuous time for Genoa. After a period of French domination from 1394–1409, Genoa came under rule by the Visconti of Milan. Genoa lost Sardinia to Aragon, Corsica to internal revolt and its Middle Eastern, Eastern European and Asia Minor colonies to the Turkish Ottoman Empire.
Genoa was able to stabilize its position as it moved into the sixteenth century, particularly thanks to the efforts of Andrea Doria, who established
