Caetani, or Gaetani, is the name of a Pisan noble family and a Roman princely family which played a great part in the history of Pisa - one of the four main historical Marine Republics of Italy (Repubbliche Marinare) - and of the papacy.
The founder of the house was Marinus I, Duke of Fondi, son of Docibilis II of Gaeta, from which the family gets its name. His successor was Constantine, who took the name Cagetanus and ruled in the latter half of the 10th century. In the late eleventh century, a descendant of his, Crescentius, was duke. This Crescentius was the father of two illustrious people: his successor, Marinus, and his son John (called Gaetanus or Coniulo) from Pisa, who was Pope Gelasius II. Marinus was succeeded by his son Crescentius, who defended his uncle the pope resolutely from imperialist attacks.
Nevertheless, the family had no more great importance in Rome until the election of Benedetto Caetani to the papacy as Pope Boniface VIII in 1294, when they at once became the most notable in the city. The pope conferred on them the fiefs of Sermoneta, Bassiano, Ninfa and San Donato (1297, 300), and the marquisate of Ancona in 1300, while Charles II of Anjou created the popes brother count of Caserta.
Giordano Loffredo Caetani by his marriage with Giovanna dell'Aquila, heiress of the counts of Fondi and Traetto, in 1297 added the name of Aquila to his own, and his grandson Giacomo acquired the lordships of Piedimonte and Gioia. The Caetani proved brave warriors and formed a bodyguard to protect Boniface VIII from his many foes. During the 14th and 15th centuries their feuds with the Colonna caused frequent disturbances in Rome and the Campagna, sometimes amounting to civil war. They also played an important role as Neapolitan nobles. In 1500 Pope Alexander VI, in his attempt to crush the great Roman feudal nobility, confiscated the Caetani fiefs and gave them to his daughter Lucrezia Borgia; but they afterwards regained them.
At present there are two lines of Caetani:
Quartetto per due violini, viola e violoncello, op. 1 From Sibley Music Library Digital Scores Collection
Quartetto per 2 violini, viola e violoncello, op. 12. From Sibley Music Library Digital Scores Collection