PICCOLOMINI  , the name of an

Italian noble family, which was prominent in Siena (q.v.) from the beginning of the 13th century onwards . In 1220 Enghelberto d'Ugo Piccolomini received the fief of Montertari in Val d'Orcia from the emperor Frederick II. as a reward for services rendered . The family acquired houses and towers in Siena and castles in the republic's territory, including Montone and Castiglione; the latter they sold to the commune in 1321 . They obtained great wealth through trade, and established counting-houses in Genoa, Venice, Aquileia, Trieste, and in various cities of France and Germany . Supporters of the Guelph cause in the civil broils by which Siena was torn, they were driven from the city in the time of Manfred and their houses demolished; they returned in triumph after the Angevin victories, were expelled once more during the brief of Charles of Anjou . But through their riotous political activity the Piccolomini lost their commercial influence, which passed into the hands of the Florentines, although they retained their palaces, castles and about twenty fiefs, some of which were in the territory of Amalfi and of great extent . Many members of the house were distinguished ecclesiastics, generals and statesmen in Siena and elsewhere; two of them were popes, viz . Aeneas Silvius Piccolomini (Pius II., q.v.) and Francesco Piccolomini (Pius III., q.v.) . See Richter, Die Piccolomini (Berlin, 1874) ; A . Lisini and A . Liberati, Albero della famiglia Piccolomini (Siena, 1899) ; and articles by A . Lisini in the Miscellanea storica senese, 3rd series 12, and 4th series, 17 and 189 .