The Balilla-class were the first submarines to be built for the Italian navy

Regia Marina

The Regia Marina dates from the proclamation of the Kingdom of Italy in 1861 after Italian unification...

 following the end of World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

. They were large ocean-going cruiser submarines designed to operate in the Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

 based in Italy's East Africa

East Africa

East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...

n colonies. The design was double-hulled and based on the German Type UE 2

German Type UE II submarine

The Type UE II submarines were a class of submarines built by the German Empire during World War I as long-range mine-layers.UE II boats carried 14 torpedoes and were armed with one 150 mm deck gun. They carried a crew of 40 and had a cruising range of about 9,400 miles...

 U-boat

U-boat

U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...

s, one of which, U-120

SM U-120

SM U-120 was a Type UE II long-range minelayer submarine of the Imperial German Navy. She was built at Hamburg, Germany, by Aktiengesellschaft Vulcan and launched on 20 June 1918...

 was supplied to the Italians as a war reparation. A 425 hp auxiliary diesel engine was installed as an extra generator.

The boats were stationed in the Mediterranean

Mediterranean Sea

The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...

 in 1940 but proved too large to be effective patrol submarines. Their only success was the sinking of the British submarine HMS Triad

HMS Triad (N53)

HMS Triad was a T-class submarine of the Royal Navy. She was laid down by Vickers Armstrong, Barrow and launched in May 1939. So far she has been the only ship of the Royal Navy to bear the name Triad.-Career:...

 by Enrico Toti on 15 October 1940. After 1941 they were used as transport submarines to supply Italian forces

Royal Italian Army (1940–1946)

This article is about the Italian Royal Army which participated in World War II.The Italian Royal Army was reformed in 1861 and lasted until 1946. The Royal Army started with the unification of Italy and the formation of the Kingdom of Italy . It ended with the dissolution of the monarchy...

 in North Africa

North Africa

North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...

. The surviving boats were scrapped after the war.

Italy

Ship	Namesake	Launched	Fate
Balilla	Giovan Battista Perasso Balilla Balilla was the nickname of Giovan Battista Perasso, a Genoese boy who started the revolt of 1746 against the Habsburg forces that occupied the city in the War of the Austrian Succession by throwing a stone on an Austrian official....	20 February 1927	Laid up April 1941
Domenico Millelire	Domenico Millelire	19 September 1927	Laid up April 1941
Antonio Sciesa	Amatore Sciesa	12 August 1928	Damaged September 1942 in Tobruk Tobruk Tobruk or Tubruq is a city, seaport, and peninsula on Libya's eastern Mediterranean coast, near the border with Egypt. It is the capital of the Butnan District and has a population of 120,000 .... , Scuttled 12 November 1942
Enrico Toti	Enrico Toti Enrico Toti Enrico Toti was an Italian cyclist, patriot and hero of World War I.Enrico lost his left leg while working for Italian railways, at the age of 24. After his injury he became a cyclist....	14 April 1928	Laid up April 1943

Brazil

was a modified version of this design built for the Brazilian Navy

Brazilian Navy

The Brazilian Navy is a branch of the Brazilian Armed Forces responsible for conducting naval operations. It is the largest navy in Latin America...

in 1927. The ship was retired in 1951.