The Italian participation to World War I confirmed that the Regia Marina was ready and well trained despite the fact that, due to the will of the Allies, the fruits of victory had been limited. Italian successes were mostly the result of a complete control of the sea and continuos actions of defense and offense conducted under the command of the “Duca degli Abruzzi” and Admiral Thaon de Revel.
The peace treaty of 1919 radically changed the balance in the Mediterranean, and although it had given Italy a better position in the Adriatic, it also created a delicate situation in the Mediterranean. This was mostly due to the new French expansions in Morocco and Syria, and the British control over Gibraltar, Egypt and Palestine.

Italian Cruisers after the Action off Calabria
After the failed Naval Conference of Geneva in 1932, where Italy had sought parity with the strongest European continental navy (France), the situation changed due to the Anglo-German and Anglo-Soviet agreements along with changes in Japanese naval policy. Thereafter, the international agreement of naval limitation expired and a period of limitation (Naval Holiday) was followed by almost complete freedom thus causing an escalation in naval rearmament.
At this point, even the Italian Navy gave an impetuous boost to new constructions; still it was not allowed to develop the armament which would have most impacted the upcoming conflict: naval aviation.
The war in Ethiopia demanded a great effort from the Regia Marina; not much in terms of combat but in logistics. This period of crisis, especially the one with Great Britain, demonstrated the importance of the naval affairs in the life of a country which had expanded to overseas dominions but who was still dependant on the British-controlled Suez canal. This situation should have suggested a different and more appropriate policy, instead it laid the tragic foundations of World War II where naval affairs were to have a great influence.
Between 1922 and 1925, the Regia Marina reorganized incorporating German and Austrian ships captured during or obtained after the war, while keeping into consideration the limitations imposed by the Treaty of Washington (1921-22).
After having radiated the older units, the Regia Marina restarted the construction program under a plan originally started by Grand Admiral Thaon de Ravel and continued by Admiral Sirianni. Taking advantage of the progress made in the area of naval contraction during the previous conflict, the first round consisted in the manufacturing of torpedo boats for which the Treaty of Washington had set no limits.
Great innovations were introduced in the area of propulsion. Engines, by this time fueled by oil, implemented super heated steam and turbines thus greatly increasing power and capable of obtaining over 30,000 H.P. per axle. At the same time, great developments took place in the area of diesel engines for both surface and submerged vessels.
In the field of armaments, all units began installing anti-aircraft guns, while the new 533 mm (21”) torpedo became the standard. Catapults appeared on larger units for the deployment of hydroplanes to be used for tactical reconnaissance and the observation of gunnery. Special attentions were dedicated to the protection of battleships against underwater attacks.
In 1932, having completed the first round of constructions, the Regia Marina allowed for the deployment of heavy cruisers of the “Trento” and “Zara” class and light cruisers of the “Condottieri” class. Also, during this period, began the construction of the destroyers of the “Sella”, “Sauro”, “Turbine” and “Freccia” class and the submarines of the “Balilla”, “Mameli”, “Vector Pisani” and “Argonauta” class.
The first large cruisers of the “Washington” class (10,000 British tons and 8” guns) were the “Trento”. Designed and built for speed (this obtained at the price of protection), they were equipped with a light armor belt, while the similarly built French vessels had no protection at all.
The Italian “10,000” which took to the sea after the “Trentos” were the “Zara”, units these with greater protection and lesser speed. This class was the best “Washington” built by Italy and had a harmonious balance of armament and protection. The fact that the enemy, in particularly advantageous circumstances, sank three of these units should not diminish their value.
For the sake of speed, protection was completely sacrificed on the light cruisers of the “Da Giussano” class. Designed by Rota, these ships were initially designated as “Esploratori” (scout).
In 1932, due to the failure of the Conference of Geneva for the limitation and control of the armament, Italy was forced to speed up the strengthening of her Navy. Starting in 1933, to partially reduce its inferiority respect to the French Navy, the Navy decided to radically rebuild the battleships Cesare, Cavour, Duilio and Doria, all veterans of World War I.
In 1934-38, as a result of the building up in the international political situation, Italy began the construction of four modern battleships; fast and well armed they were named Vittorio Veneto, Littorio, Roma, and Impero.
While the core of the fleet was been rebuilt, Italy placed into service cruisers, and numerous destroyers, torpedo boats and submarines.
The last of the sever “10,000”, the Bolzano, was based on the Trentos, but it had much improved characteristics. A clear improvement over the first cruisers of the “Condottieri” class, was the release into service of the units type “Montecuccoli” and “Duca d’Aosta”. Even better were the two “Duca degli Abruzzi”, which during the period 1940-43 proofed themselves strong and with excellent performances.
The last improved version of the cruiser class “Condottieri” was not completed, due to the bad turn taken by the war. The Ciano and Venezia would have been based on the “Duca degli Abruzzi” class, thus bringing the total number of light cruisers built by the Regia Marina between the two wars to fourteen.
In 1939-40 began the construction of 12 cruisers of the class “Capitani Romani”; ships these with characteristics similar to the “grandi esploratori” (super destroyers) and equipped with efficient anti-torpedo boat and anti-aircraft armament. Constructions of these units were delayed due to the shortage of raw materials during the war, and up to September 8th, 1943, only three units (Attilio Regolo, Scipione Africano, Pompeo Magno) had entered service.
In conclusion, the Regia Marina, which had planned to complete its building programs in 1942, entered the war on June 10th, 1940 with about 700,000 tons including 19 modern cruisers, for what was to be the harsh testing ground of World War II.