[2] In 1619, Benedetto's brother and three uncles founded a bank in Genoa, 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.

After his participation to the 1683 Battle of Vienna, he was granted the Duchy of Syrmia (around Ilok Castle, now divided between Serbia and Croatia) and the dignity of prince of the Holy Roman Empire by Leopold I.

Antonio Maria Erba-Odescalchi, Pope Innocent's great-grandnephew and Cardinal Benedetto Erba-Odescalchi's nephew, was a Doctor in Civil and Canon Law (Milan 1733), which allowed him to pursue a career in the Papal Court in Rome as a church lawyer.

The Pope's grand-nephew Cardinal Benedetto Erba Odescalchi held a doctorate in Civil and Canon Law (Pavia, 1700), and was Papal Nuncio in Poland from 1712 to 1714.

[5] Carlo Odescalchi, S.J.,[6] was the son of Prince Baldassare Erba-Odescalchi, and Valeria Caterina Giustiniani.

On 10 March 1823 Odescalchi was created a cardinal and named Archbishop of Ferrara; he resigned the diocese in 1826 to pursue a higher career in the Papal Curia as Prefect of the Congregation of Bishops and Regulars.

The family owns the Palazzo Odescalchi in Rome and the Orsini-Odescalchi Castle in Bracciano, as well as large estates in Italy.