Erba-Odescalchi, or Odescalchi, is the name of an Italian noble family of princely rank. With the election of Benedetto Odescalchi as Pope Innocent XI in 1676, members of his family advanced in social status from bankers to members of the elite.
Benedetto Odescalchi reigned as Pope Innocent XI until 1689. As the last male heir to the family, their fortune passed to the descendants of his sister, Lucrezia Odescalchi, who had married Alessandro Erba in 1621. The Erba family is allegedly descended from Enrico Erba, an Imperial vicar in Milan, around 1165. The title of Prince of the Holy Roman Empire was conferred on their grandson Baldassare Erba-Odescalchi in 1714, along with the title, Duke of Syrmia in the Kingdom of Hungary and the qualification of Serene Highness. Other religious members of the family were Cardinals Benedetto Erba Odescalchi and Carlo Odescalchi.
In 1619, Benedetto's brother and three uncles founded a bank in Genoa, the banking capital of Catholic Europe, which grew into a successful money-lending business. After completing his studies in grammar and letters, the 15-year-old Benedetto moved to Genoa to take part in the family business as an apprentice. The family established lucrative financial transactions with clients in major Italian and European cities, such as Nuremberg, Milan, Kraków, and Rome.
The head of the family now bears titles including Prince Odescalchi, Duke of Syrmium, and Prince of Bassano. Prince Odescalchi is a Hereditary Magnate of Hungary and Grandee of Spain. The family owns the Palazzo Odescalchi in Rome, the Orsini-Odescalchi Castle in Bracciano, as well as large estates in Italy, Croatia (Ilok Castle) and Hungary. The castle in Bracciano was originally an Orsini family fortress until it was sold to pay debts.
The Princely family is currently represented by Prince Carlo Odescalchi, Prince of the Holy Roman Empire, Duke of Syrmium, etc. (b.1954), whose heir is his son Prince Baldassare Odescalchi (b.1993).
- Original 1922 Almanach de Gotha (edited by Justice Perthes) entry for the Odescalchi family, link to the original universally-recognised genealogical reference document, with details of family honours
- Theroff's Online Gotha – entry for the Odescalchi family, with references to current, legitimate members of the princely family
- A. von Reumont, Geschichte der Stadt Rom (Berlin, 1868)