1911 Encyclopædia Britannica/Odescalchi-Erba

ODESCALCHI-ERBA, the name of a Roman princely family of great antiquity. They are supposed to be descended from Enrico Erba, imperial vicar in Milan in 1165. Alessandro Erba married Lucrezia Odescalchi, sister of Pope Innocent IX., in 1709, who is believed to have been descended from Giorgio Odescalchi (floruit at Como in 1290). The title of prince of the Holy Roman Empire was conferred on Alessandro in 1714, and that of duke of Syrmium in Hungary in 1714, with the qualification of “serene highness.” The head of the family now bears the titles of Fürst Odescalchi, duke of Syrmium, prince of Bassano, &c., and he is an hereditary magnate of Hungary and a grandee of Spain; the family, which is one of the most important in Italy, owns the Palazzo Odescalchi in Rome, the magnificent castle of Bracciano, besides large estates in Italy and Hungary.

See A. von Reumont, Geschichte der Stadt Rom (Berlin, 1868), and the Almanach de Gotha.