Cavour agreed to let France have the regions of Nice and Savoy after they went to war against Austria in 1859 to help unite Italy. Garibaldi freed Sicily from the Kingdom of the Two Sicilies and then took control of the mainland, uniting the entire kingdom. While Venetia and the Papal States were not yet part of Italy, Austria gave up Venetia in 1866 and Italian forces invaded the Papal States in 1870, with Rome becoming the capital of the newly united nation.