Faced with that choice, the Duke of Savoy, Victor Amadeus, ended his persecution of the Vaudois and joined the Alliance. His primary objective was to regain Pinerolo and Casale, which were strategic locations controlling access to his capital, Turin. A French force, led by Nicolas Catinat, defeated a Savoyard army at Staffarda in August 1690. Savoy was nearly overrun in late 1691 but was saved by reinforcements from Spain, Bavaria and Brandenburg-Prussia. In 1692, Victor Amadeus made a short-lived invasion of the Dauphiné, the only Allied incursion into French territory during the entire war.