GAETA, a seaport and episcopal see of Lazio, Italy, province of Rome (anc. Caietae Portus), 5 m. by rail west of Formia (q.v.). Pop. (1931) 10,423, town; 22,882, commune. It occupies a lower projecting point of the promontory which forms the south west extremity of the Bay of Gaeta. The tomb of Munatius Plancus, on the summit of the promontory (see CAIETAE PORTUS), is now a naval signal station. The harbour, well sheltered except on the east, is entirely a naval station. To the north-west is the suburb of Elena. Above the town is a castle erected by the Angevin kings, and strengthened at various periods. The cathedral of St. Erasmus (S. Elmo), consecrated in 1106, has a fine campanile begun in 86o and completed in 1279, and a nave and four aisles; the interior has, however, been modernized. Opposite the door of the cathedral is a candelabrum with interesting sculptures of the end of the 13th century. Behind the high altar of the cathedral is the banner sent by Pope Pius V. to Don John of Austria, the victor of Lepanto. The constable of Bourbon, who fell in the sack of Rome of 1527, is buried here. Close to the church of La Trinita is the Montagna Spaccata, where a vertical fissure from 6 to 15 ft. wide runs right down to the sea-level. Over the chasm is a chapel del Crocefisso, the mountain having split, it is said, at the death of Christ.
During the break-up of the Roman empire, Gaeta, like Amalfi and Naples, would seem to have established itself as a practically independent port and to have carried on a thriving trade with the Levant. Its history, however, is obscure until, in 839, it appears as a lordship ruled by hereditary hypati or consuls. According to tradition, the Caetani or Gaetani family (q.v.) is descended from these hypati. In 844 the town fell into the hands of the Arabs, but four years later they were driven out with help supplied by Pope Leo IV. In 875 Pope John VIII. gave it to the count of Capua as a fief of the Holy See, which had long claimed jurisdic tion over it. In 877, however, the hypatus John (Ioannes) II. succeeded in recovering the lordship, which he established as a duchy under the suzerainty of the East Roman emperors. In the IIth century the duchy fell into the hands of the Norman counts of Aversa, afterwards princes of Capua, and in 1135 it was annexed to his kingdom by Roger of Sicily. Its fortifications were strengthened in the 15th century. On the 3oth of September i 7o7 it was stormed, after a three months' siege, by the Austrians under Daun; and on the 6th of August 1734 it was taken, after a siege of four months, by French, Spanish and Sardinian troops. The fortifications were again strengthened; and in 1 799 it was tempo rarily occupied by the French. On the 18th of July 1806 it was captured, after an heroic defence, by the French under Massena; and on the 18th of July 1815 it capitulated, after a three months' siege, to the Austrians. In November 1848 Pope Pius IX., after his flight in disguise from Rome, found a refuge at Gaeta, where he remained till the 4th of September, 1849. In 1860, it was the scene of the last stand of Francis II. of Naples (q.v.) against the forces of United Italy. (T. A.) See G. Caetani, Caietanorum Genealogia (Perugia, 192o) ; Rocca S. Casciano, i., ii. (1927), Epistolarium Honorati Caietani, ib. (192 7) ; Domus Caietana Regesta Chartarum ib., i., ii. (1922-26), for the his tory of the family.