List of heavy cruisers of Italy

The Regia Marina had initially intended to build six cruisers, which would operate as two three-ship divisions, but Pola of the Zara class was used as the fleet flagship while the Conte di Cavour-class battleships were being rebuilt, so a seventh ship was ordered.

All seven ships saw extensive service in the Mediterranean Sea during World War II, where they repeatedly engaged elements of the British Royal Navy.

[4] While the Trentos were still under construction, elements of the Italian naval command began to doubt the effectiveness of the new vessels, which sacrificed armor protection in favor of very high speeds.

They advocated a more balanced design that would incorporate more comprehensive armor, while retaining the battery of eight 203 mm guns and a speed of at least 32 knots (59 km/h; 37 mph).

[6][7] The heavy armor of the Zaras made them the best-protected cruisers built by any navy until the United States' Des Moines class, laid down in 1945.

[8] The four ships all saw action at Calabria, Cape Spartivento, and Cape Matapan; at the last engagement, Pola was disabled by a torpedo from a Swordfish torpedo bomber launched by the British aircraft carrier HMS Formidable; Zara and Fiume were detached from the rest of the fleet to protect Pola, and all three and a pair of destroyers were sunk in a close-range night engagement with the battleships Barham, Valiant, and Warspite.

While the ship was moored in La Maddalena on 10 April 1943, a major attack from United States Army Air Forces heavy bombers sank Trieste and hit Gorizia with three bombs, inflicting serious damage.

[9][10] By 1928, the Italian navy had begun rebuilding the Conte di Cavour-class battleships, and as a result, Pola was completed with an enlarged bridge so she could temporarily serve as the fleet flagship.

The design requirements for the new vessel reverted to those adopted for the Trentos, as the senior leaders of the navy continued to believe that speed was more important than armor.