It was brought into existence in 1921, and initially consisted of a few former Austro-Hungarian Navy vessels surrendered at the conclusion of World War I and transferred to the new nation state under the terms of the Treaty of Saint-Germain-en-Laye.

Significant new acquisitions began in 1926 with a former German light cruiser, followed by the commissioning of two motor torpedo boats (MTBs) and a small submarine flotilla over the next few years.

The following year, a British-made flotilla leader was commissioned with the idea that the KM might be able to operate in the Mediterranean alongside the British and French navies.

Over the next two years, the fleet was significantly strengthened by the acquisition of three French-designed destroyers, marking the high point of Yugoslav naval strength.

While the KM was largely captured by Italian forces during the German-led Axis invasion of Yugoslavia in April 1941, a few of its vessels, aircraft and their crews escaped and served in the Mediterranean under Royal Navy control during the remainder of World War II.

By the end of that month, the "sailor's councils" that had been formed aboard Austro-Hungarian warships at the main base of Pola had decided that they would leave their ships by 1 November, regardless of the political discussions that were ongoing.

The National Council appointed Rear Admiral Dragutin Prica as the Navy Commissioner and Captain Janko Vuković de Podkapelski as fleet commander.

As Prica was ill, the National Council appointed Captain Metodije Koch as Navy Commissioner and promoted him to rear admiral on 2 November.

Italy immediately began to occupy the former Austro-Hungarian coast and offshore islands, and demanded the handover of the vessels then under the control of the National Council.

During that month, the Italians finally disembarked all remaining crew from former Austro-Hungarian vessels, leaving the nascent KSCS Navy without any ships.

The final fate of the former Austro-Hungarian vessels was determined by the Allied powers during the Paris Peace Conference, which also decided territorial disagreements between Italy and the KSCS.

[4] In October 1920, the question was finally settled when the Treaty of Saint-Germain-en-Laye provided for the transfer of the obsolete coastal defence ship SMS Kronprinz Erzherzog Rudolf, eight 250t-class torpedo boats, four older Kaiman-class torpedo boats, the repair ship Cyclop, the water carriers Najade and Nixe, the salvage vessel Gigant, three tugs, the yacht Dalmat, four hulks, four river monitors (Bosna, Enns, Körös and Bodrog), one motor launch, three river tugs, 16 small tenders, and a significant number of coal and oil lighters.

[11] The service's initially unrealistic expansion goals of 24 destroyers and 24 submarines were soon shelved, and by the end of 1923 the fleet consisted of eight 250t-class torpedo boats, four Kaiman-class torpedo boats, six Galeb-class minelayers, four Schichau-class minesweepers, the water carrier Perun (ex-Cyclop), the yachts Vila (ex-Dalmat) and Lada (ex-Quarnero), the training ship Vila Velebit, the salvage vessel Moćni (ex-Gigant), and four tugs.

It was home to the Tivat Arsenal, a naval yard which was expanded to repair and overhaul larger vessels; it included two floating docks, one of 2,000 long tons (2,032 t) and one of 7,000-long-ton (7,100 t) capacity.

The following year, two British-built Thornycroft Uskok-class motor torpedo boats (MTBs) were acquired, named Uskok and Četnik, and a base was built for them at Šibenik.

[16] In May and June 1929, a squadron, under the command of Prica and consisting of Dalmacija, Hvar and the two Hrabri-class submarines, visited Malta, Corfu and Bizerte.

Also in 1929, the former Austro-Hungarian water carrier Najade, now named Sitnica, was re-employed as an auxiliary for the submarine flotilla, despite its lack of a workshop for repair work.

The appointment of a chief of the Maritime Air Force in 1930 signified the separation of naval aviation from army control, with a strength of around 1,000 officers and men, of whom about 80 were pilots.

The long endurance requirement reflected Yugoslav plans to deploy the ships into the central Mediterranean, where they would be able to operate alongside French and British warships.

In the same year, Dubrovnik sailed to the Black Sea then visited several ports in the Mediterranean with King Alexander and Queen Marie aboard.

By the end of that year, the KM consisted of 27 surface combatants, four submarines, and around a dozen auxiliary vessels, crewed by a total of 487 officers and about 5,000 men.

However, in 1936 the only vessels ready for war service were Dubrovnik and the four submarines, and the navy was only considered capable of patrol duties and coastal surveillance, minelaying and minor raids against enemy shipping.

[33] In 1939, the British observed that the commander-in-chief of the Yugoslav Navy, Polić, was "amiable but ignorant" and had little technical knowledge regarding naval matters.

On the same day, three KM Dornier Do 22s and Rogožarski SIM-XIV-Hs provided air cover while the Galeb-class minelayer Jastreb laid a minefield off Budva harbour.

[41] The next day, Italian bombers struck a number of Yugoslav naval and seaplane bases along the coast, destroying and damaging several aircraft.

Drava was hit by several of them but they were unable to penetrate her 300-millimetre (12 in) thick deck armour, until by chance, one put a bomb straight down the funnel, killing 54 of the 67 crew.

The remaining three monitors were scuttled by their crews later on 12 April as German and Hungarian forces had occupied their bases and the river systems upon which they operated.

[43] However, Zagreb was blown up and scuttled at the Bay of Kotor by two junior officers, Sergej Mašera and Milan Spasić, to prevent her capture.

The force was led by Captain Ivan Kern, who was attached to the Yugoslav government-in-exile in London, and operated with the British Mediterranean Fleet from bases in Malta and Alexandria.

[52] A number of the captured Yugoslav warships, notably Dubrovnik, Beograd and the repaired Ljubljana, were employed by the Italian Regia Marina until the armistice in 1943, whereupon the German Kriegsmarine, and to a lesser extent the Navy of the Independent State of Croatia, appropriated the surviving vessels for their own fleets.