Cavour's tenure as naval minister was marked by a more aggressive foreign policy; Cavour also served as the Prime Minister of Sardinia. Under his direction the country joined the British and French during the Crimean War of 1853–1855, though the Sardinian contribution to the war was almost entirely on land; a small squadron consisting of "Carlo Alberto" and several paddle steamers were sent to support the expeditionary army. The war nevertheless provided an opportunity to seek closer ties with France and experience operating warships under wartime conditions. In 1859, he engineered the Second Italian War of Independence, a major step toward Italian unification, relying on a secret alliance with France to defeat the larger Austrian Empire. During the latter conflict, the Sardinian fleet operated with the French Navy against Austrian ships in the Adriatic. At that time, the Sardinian fleet consisted of two screw-driven frigates, four sail frigates, two sail corvettes, six brigs, and eight paddle steamers. The powerful French squadron, including six screw ships of the line and three ironclad floating batteries, compelled the Austrians to retreat to Pola. The two fleets began preparations for joint amphibious assaults on the Dalmatian coast of Austria, but victories on land at the Battles of Magenta and Solferino ended the war before the landings could be conducted.