Re d'Italia (King of Italy) was the lead ship of the Re d'Italia-class armored frigates built in the United States for the Italian Regia Marina (Royal Navy) in the early 1860s.

She was laid down at the William H. Webb Shipyard in New York in November 1861, was launched in April 1863, and was completed a year later in September 1864; the two Re d'Italia-class ships were the only Italian ironclads built in the United States.

Re d'Italia initially served as the flagship of the Italian fleet, though she was replaced by the turret ship Affondatore shortly before the Battle of Lissa in 1866.

Re d'Italia quickly rolled over and sank, taking some 400 of her crew with the ship, including her captain, Emilio Faà di Bruno.

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.

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

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Principe di Carignano to determine whether he should sortie to engage Tegetthoff, but by that time, the Austrians had withdrawn, making the decision moot.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

[9] The next morning, Persano ordered another attack; four ironclads would force the harbor defenses at Vis while Re d'Italia and the rest of the fleet would attempt to suppress the outer fortifications.

[10] Shortly before the action began, Persano decided to leave Re d'Italia and transfer to Affondatore, though none of his subordinates on the other ships were aware of the change.

[11] Re d'Italia's captain, Emilio Faà di Bruno, attempted to escape from the melee, but he could only steer his ship using her engines.