The ship, named for the island of Sardinia, was laid down in La Spezia in October 1885, launched in September 1890, and completed in February 1895.

She was armed with a main battery of four 340 mm (13.5 in) guns and had a top speed of 20.3 knots (37.6 km/h; 23.4 mph)—albeit at the cost of armor protection—and she was one of the first warships to be equipped with a wireless telegraph.

She took part in the Italo-Turkish War of 1911–1912, where she escorted convoys to North Africa and supported Italian forces ashore by bombarding Ottoman troops.

During World War I, Sardegna served as the flagship of the naval forces defending Venice against a possible attack from the Austro-Hungarian Navy, which did not materialize.

Specific figures for her cruising radius have not survived, but the ships of her class could steam for 4,000 to 6,000 nautical miles (7,400 to 11,100 km; 4,600 to 6,900 mi) at a speed of 10 knots (19 km/h; 12 mph).

Close-range defense against torpedo boats was provided by a battery of sixteen 120 mm (4.7 in) guns in casemates in the upper deck, eight on each broadside.

[1] After entering service, Sardegna was assigned to the 2nd Division of the Reserve Squadron as its flagship, along with the older ironclad Ruggiero di Lauria and the torpedo cruiser Aretusa.

[2] Sardegna joined the ironclads Re Umberto, Ruggiero di Lauria, and Andrea Doria and the cruisers Stromboli, Etruria, and Partenope for a visit to Spithead in the United Kingdom in July 1895.

[9] At the time, Sardegna and her two sisters were assigned to the Training Division, along with the old armored cruiser Carlo Alberto, under the command of Rear Admiral Raffaele Borea Ricci D'Olmo.

By the morning of the 4th, the ships' gunfire had silenced the guns in the fort, allowing landing forces to go ashore and capture the city.

[15] The following month, Sardegna and her sisters, along with six torpedo boats, escorted a convoy carrying an infantry brigade to Buscheifa, one of the last ports in Libya still under Ottoman control.

[16] The Training Division then returned to Italy, where they joined the escort for another convoy on 3 August, this time to Zuara, the last port in Ottoman hands.

The ships covered the landing two miles east of Zuara two days later, which was joined by supporting attacks from the west and south.

[20] Instead, Revel decided to implement a blockade at the relatively safer southern end of the Adriatic with the main fleet, while smaller vessels, such as the MAS boats, conducted raids on Austro-Hungarian ships and installations.

The Northern Adriatic Naval Forces also included the two old Ammiraglio di Saint Bon-class battleships, two cruisers, and several smaller craft.

[22] The reason for her withdrawal was the major Italian defeat at the Battle of Caporetto; the German and Austro-Hungarian advance threatened to continue to Venice.