In January 1940, Ljubljana struck a reef off the port of Šibenik and was still under repair when the German-led Axis invasion of Yugoslavia commenced in April 1941.

The Royal Italian Navy operated Beograd and Ljubljana as convoy escorts between Italy, the Aegean Sea, and North Africa, under the names Sebenico and Lubiana respectively.

In 1973, the President of Yugoslavia and wartime Partisan leader Josip Broz Tito posthumously awarded the two officers who scuttled Zagreb with the Order of the People's Hero.

The Royal Yugoslav Navy decided to build three such flotilla leaders, ships that could reach high speeds and have long endurance.

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

In 1934, buoyed by a special credit of 500 million dinars for an enlargement and modernisation program,[4] the KM decided to acquire three such destroyers to operate in a division led by Dubrovnik.

[8][9][10] They carried 120 tonnes (120 long tons) of fuel oil,[8] which gave them a radius of action of 1,000 nautical miles (1,900 km; 1,200 mi).

[8][11][12] Secondary armament consisted of four Škoda 40 mm (1.6 in) L/67 anti-aircraft guns[13] in two twin-gun mounts, located on either side of the aft shelter deck.

Their only significant pre-war task was undertaken by Beograd in May 1939 and involved transporting a large portion of Yugoslavia's gold reserve to the United Kingdom for safekeeping.

[20] When Yugoslavia was invaded by the German-led Axis powers on 6 April 1941, Beograd and Zagreb were allocated to the 1st Torpedo Division at the Bay of Kotor along with Dubrovnik,[21] but Ljubljana was still under repair at Šibenik.

[16][17] A 1967 French film, Flammes sur l'Adriatique (Adriatic Sea of Fire), portrayed the scuttling of Zagreb and the events leading up to it.

[32] In 1973, the President of Yugoslavia and wartime Partisan leader Josip Broz Tito posthumously awarded the Order of the People's Hero to the two officers who scuttled Zagreb.