The Wars of Castro were a series of conflicts during the mid-17th century revolving around the ancient city of Castro (located in present-day Lazio, Italy), which eventually resulted in the city's destruction on 2 September 1649. The conflict was a result of a power struggle between the papacy – represented by members of two deeply entrenched Roman families and their popes, the Barberini and Pope Urban VIII and the Pamphili and Pope Innocent X – and the Farnese dukes of Parma, who controlled Castro and its surrounding territories as the Duchy of Castro. Precursors Papal politics of the mid-17th century were complicated, with frequently shifting military and political alliances across the Catholic world. While it is difficult to trace the precise origins of the feud between the duchy of Parma and the papacy, its origins can be looked for in political maneuverings occurring in the years or even decades preceding the start of military action. In 1611 a group of conspirators, nobles from Modena and Mantua, was accused of devising a plot to assassinate Ranuccio I Farnese, Duke of Parma and other members of the Farnese family in Parma. In reality, the plot had been "uncovered" when a prisoner (being held for unrelated crimes) confessed to it and implicated members of various noble houses. Though the accusations were likely untrue, 100 of the "conspirators" were tortured and eventually executed in Parma's main square in 1612. Many of their estates were confiscated leaving a large number of now legitimately discontented nobles. Until his death in 1622, Ranuccio remained paranoid about future assassination attempts and about curses from witches and heretics. He persecuted "witches" and alleged conspirators savagely and even had his own mistress, Claudia Colla, burned to death. He remained convinced that other noble families were plotting his downfall. However, tensions between the Farnese and other Italian nobility were not limited to local events in Parma. Historian Leopold von Ranke gives an account of a 1639 visit to Rome by Odoardo Farnese, Duke of Parma and Piacenza. The Duke arrived in Rome to great fanfare - he was given gifts and escorted around the city by Pope Urban's Cardinal-nephews, Antonio Barberini and Francesco Barberini. But the Duke refused to pay due deference to the Pope's other nephew; the newly appointed Prefect of Rome, Taddeo Barberini. As the Duke prepared to leave, he suggested that an escort from the city (ordinarily reserved