Though its navy sacked the port of Palermo in 1063, two centuries later it was unable to hold off its Genoese rivals, who defeated it at the battle of Meloria.  
Though its navy sacked the port of Palermo in 1063, two centuries later it was unable to hold off its Genoese rivals, who defeated it at the battle of Meloria.  Despite its Ghibelline leanings, which provided it with imperial support, it was unable to ward off its foes on land either, as it came under increasing hostile pressure from Lucca to the northeast.  The church council held here in 1409 resulted the uneasy coexistence of three rival popes.  Though it reasserted its rights for a brief period after the arrival of the French in 1494, the silting up of its harbor and the Florentine conquest in 1406 ended its existence as an independent power. FTP, identify this city in the valley of the Arno, the birthplace of Galileo but more famous for the uneven foundations of its campanile.
Though its navy sacked the port of Palermo in 1063, two centuries later it was unable to hold off its Genoese rivals, who defeated it at the battle of Meloria.  
Pisa