Though the "Principe di Carignano"s were the second class of Italian ironclads, the foreign shipyards that built the subsequent and es completed almost all of those vessels before the first member of the "Principe di Carignano" class entered service. "Principe di Carignano" was the only member of the class to enter service in time to take part in the Third Italian War of Independence against the Austrian Empire. The war broke out in June 1866, as Italy, which had allied with Prussia, sought to take advantage of the Austro-Prussian War to seize Austrian-controlled Venice. After initially remaining in port, the Italian fleet under Admiral Carlo Pellion di Persano launched an attack on the island of Lissa in mid-July; the Austrian fleet under Rear Admiral Wilhelm von Tegetthoff sortied to mount a counterattack, which resulted in the Battle of Lissa on 20 July. "Principe di Carignano", the lead ship in the line of battle, was not heavily engaged, as Tegetthoff had attacked the Italian fleet at its center. "Principe di Carignano" tried to attack the wooden vessels of the Austrian fleet without success before Persano broke off the action; the Italian fleet had become disorganized and two ships, and had been sunk.