Castelfidardo was the third of four Regina Maria Pia-class ironclad warships built in French shipyards for the Italian Regia Marina (Royal Navy) in the 1860s.

Her career was limited after the war, owing to the emergence of more modern ironclads and a severe reduction in the Italian naval budget following their defeat at Lissa.

Persano claimed he was simply waiting on the ironclad ram Affondatore, en route from Britain, but his inaction weakened morale in the fleet, with many of his subordinates openly accusing him of cowardice.

[3] Rear Admiral Wilhelm von Tegetthoff brought the Austrian fleet to Ancona on June 27, in an attempt to draw out the Italians.

Castelfidardo was one of the few ironclads fit for action, so she, Regina Maria Pia, San Martino, and Principe di Carignano formed up to prepare to attack Tegetthoff's ships.

Persano held a council of war aboard Principe di Carignano to determine whether he should sortie to engage Tegetthoff, but by that time, the Austrians had withdrawn, making the decision moot.

The Minister of the Navy, Agostino Depretis, urged Persano to act and suggested the island of Lissa, to restore Italian confidence after their defeat at the Battle of Custoza the previous month.

[5] Castelfidardo was at that time assigned to the 1st Division, commanded by Admiral Giovanni Vacca, along with the ironclads Ancona and Principe di Carignano, the divisional flagship.

Persano then sent Vacca's division to Vis to force the harbor defenses, but by the time they arrived, night was approaching, and so he cancelled the attack.

[7] The next morning, Persano ordered the ironclad Formidabile to enter the harbor Vis and attack the Madonna battery, supported by Castelfidardo and the rest of the 1st Division.

He failed to ram any Italian vessels on the first pass, so he turned back toward Persano's ships, and took Re d'Italia, San Martino, and Palestro under heavy fire.

After the battle, Vacca replaced Persano; he was ordered to attack the main Austrian naval base at Pola, but the war ended before the operation could be carried out.

The cuts were so severe that the fleet had great difficulty in mobilizing its ironclad squadron to attack the port of Civitavecchia in September 1870, as part of the wars of Italian unification.

[1] For the annual fleet maneuvers held in 1885, Castelfidardo served in the "Eastern Squadron", joined by the ironclad Principe Amedeo, the corvette Amerigo Vespucci, a sloop, and four torpedo boats.

[15] On 10 June, the annual fleet maneuvers began; Castelfidardo was assigned to the "defending squadron", along with the ironclads Enrico Dandolo, Palestro, and Affondatore, the protected cruiser Dogali, and several smaller vessels.

The first half of the maneuvers tested the ability to attack and defend the Strait of Messina, and concluded in time for a fleet review by King Umberto I on the 21st.