Pisa, at that time overlooking the sea at the mouth of the Arno, reached the pinnacle of its glory between the 12th and 13th centuries, when its ships controlled the Western Mediterranean. Rivalry between Pisa and Genoa grew worse in the 12th century and resulted in the naval Battle of Meloria (1284), which marked the beginning of Pisan decline; Pisa renounced all claim to Corsica and ceded part of Sardinia to Genoa in 1299. Moreover, the Aragonese conquest of Sardinia, which began in 1324, deprived the Tuscan city of dominion over the "Giudicati" of Cagliari and Gallura. Pisa maintained its independence and control of the Tuscan coast until 1409, when it was annexed by Florence.