Born in Pitigliano,[1] she was the daughter of Lodovico Orsini and Giulia Conti. In 1513, an engagement contract between Orsini and Pier Luigi Farnese was drawn up, and in 1519 the wedding was celebrated at Valentano. Her husband was the illegitimate son of Pope Paul III and Silvia Ruffino. The couple had five children, three of whom would have further progeny.
When Cardinal Alessandro Farnese became Pope Paul III in 1534, he made his son Pier Luigi captain-general of the Church, in 1537, Duke of Castro, and finally in 1545, Duke of Parma and Piacenza. Gerolama remained in Rome and maintained the family presence at the court of the Pope. She was described as a sensible person capable of making important decisions when necessary, close to the Pope and the interests of her sons. She lived a retired life, but was always actively engaged in maintaining the political interest of her sons.
She was widowed in 1547 and remained in Rome. When Pope Paul III died in 1549, Gerolama unsuccessfully attempted to work for the candidacy of a Pope beneficial to the Farnese family. In 1550, Gerolama was appointed the regent-governor of the Duchy of Castro in the absence of her son.[1] Castro was occupied by Papal troops the same year. Gerolama maintained her regency by not resisting, and yet continuing to exert her authority while working for the end of the Papal occupation, and finally managed to achieve the end of the Papal occupation in 1552.[1] Her regency ended when she was informed of the death of her son Orazio in 1553, and she departed for Parma, where she settled for the rest of her life.[1]
