Italy and France, next to the isle of Giglio (Battle of Giglio), in front of Tuscany; the Genoese lost 25 ships, while about a thousand sailors, two cardinals, and one bishop were taken prisoner. After this major victory, the council in Rome failed, but Pisa was excommunicated. This extreme measure was only removed in 1257. Anyway, the Tuscan city tried to take advantage of the favourable situation to conquer the Corsican city of Aleria and even lay siege to Genoa itself in 1243. The Ligurian republic of Genoa, however, recovered fast from this blow and won back Lerici, conquered by the Pisans some years earlier, in 1256. The great expansion in the Mediterranean and the prominence of the merchant class urged a modification in the city's institutes. The system with consuls was abandoned, and in 1230, the new city rulers named a capitano del popolo ("people's chieftain") as civil and military leader. Despite these reforms, the conquered lands and the city itself were harassed by the rivalry between the two families of Della Gherardesca and Visconti. In 1237 the archbishop and the Emperor Frederick II intervened to reconcile the two rivals, but the strains continued. In 1254, the people rebelled and imposed 12 ("People's Elders") as their political representatives in the commune. They also supplemented the legislative councils, formed of noblemen, with new People's Councils, composed by the main guilds and by the chiefs of the People's Companies. These had the power to ratify the laws of the Major General Council and the Senate. Decline The decline is said to have begun on August 6, 1284, when the numerically superior fleet of Pisa, under the command of Albertino Morosini, was defeated by the brilliant tactics of the Genoese fleet, under the command of Benedetto Zaccaria and Oberto Doria, in the dramatic naval Battle of Meloria. This defeat ended the maritime power of Pisa and the town never fully recovered; in 1290, the Genoese destroyed forever the Porto Pisano (Pisa's port), and covered the land with salt. The region around Pisa did not permit the city to recover from the loss of thousands of sailors from the Meloria, while Liguria guaranteed enough sailors to Genoa. Goods, however, continued to be traded, albeit in reduced quantity, but the end came when the Arno started to change course, preventing the galleys from reaching the city's port up the river. The nearby area also