About 2,000 tons heavier, they had significantly better protection, and upgraded power-plants to maintain the required high speed.

The final pair, the Luigi di Savoia Duca degli Abruzzis completed the transition, sacrificing a little speed for good protection (their armour scheme was the same of the Zara-class heavy cruisers) and for two more 6-inch /55 guns.

The ships of the first two subclasses (with the exception of Luigi Cadorna) were all lost by 1942, primarily to enemy torpedoes (with Bartolomeo Colleoni sunk by destroyers at the Battle of Cape Spada after being crippled by HMAS Sydney, Alberico da Barbiano and Alberto di Giussano suffering a similar fate at in a night action of the Battle of Cape Bon, Giovanni delle Bande Nere sunk by British submarine HMS Urge, and Armando Diaz sunk by the British submarine HMS Upright) that led many authors (including Preston) to question their real value as fighting ships.

The subsequent vessels fared considerably better with all surviving the war, except Muzio Attendolo (torpedoed in August 1942 and sunk by an Allied bombing in December 1942).

After the end of the war, Eugenio di Savoia and Emanuele Filiberto Duca d'Aosta were given to the Greek Navy and the Soviet Navy respectively as war reparations; Luigi Cadorna was quickly stricken, Raimondo Montecuccoli became a training ship, and the Luigi di Savoia Duca degli Abruzzi subclass served on in the Marina Militare until the 1970s, with Giuseppe Garibaldi becoming the first European guided missile cruiser in 1961.