GIGLIO, an island of Italy (anc. Igilium), off the southwest coast of Italy, in the province of Grosseto, II m. to the west of Monte Argentario. It measures about 5 m. by 3 and its highest point is 1,634 ft. above sea-level. Pop. (1931) of Giglio Castello, the village at the highest point, 1,004; of Giglio Porto (at the harbour), 944. Granite was quarried here by the Romans and is still used; the island is fertile, and produces wine and fruit, the cultivation of which has taken the place of the forests of which Rutilius spoke when it served as a place of refuge from the barbarian invaders. Charlemagne gave it to the abbey of Tre Fontane at Rome, with a considerable part of the Maremma. From 1264 to 1406 it belonged to Pisa, then to Florence, then, after being seized by the Spanish fleet, it was ceded to Antonio Piccolomini, nephew of Pius II. In 1558 it was sold to Eleonora, wife of Cosimo I. of Florence.
See Archduke Ludwig Salvator, Die Inset Giglio (Prague, 190o) .