Considered a somewhat insignificant part of the naval warfare in World War II, it nonetheless saw interesting developments, given the specificity of the Dalmatian coastline.

Naval operations in the Adriatic consisted mostly of transport organisation through the ports of Taranto, as well as coastal bombardment in support of the landings on the Albanian coast.

[1] When Italy entered World War II, on 10 June 1940, the Italian Navy's main naval bases in the Adriatic Sea were Venice, Brindisi, and Pola.

Faced with the formidable Regia Marina, its role was primarily limited to patrol and convoy escort duties in the Aegean Sea.

This was essential both for the completion of the Army's mobilization and the overall resupply of the country, the convoy routes being threatened by Italian aircraft and submarines operating from the Dodecanese Islands.

[3] Although the Regia Marina suffered severe losses in capital ships from the British Royal Navy during the Taranto raid, Italian cruisers and destroyers continued to operate covering the convoys between Italy and Albania.

The only surface engagement between the Regia Marina and the Royal Navy occurred on the night of 11–12 November 1940, when a British squadron of three light cruisers and two destroyers attacked an Italian return convoy consisting of four merchant ships escorted by the auxiliary cruiser Ramb III and the torpedo boat Nicola Fabrizi, in the Battle of the Strait of Otranto.

In March 1941, Fairey Swordfish torpedo bombers of the Fleet Air Arm, based in Paramythia, Greece, raided the harbour of Valona multiple times, sinking one merchant ship, one torpedo boat and the hospital ship Po; the Regia Aeronautica then discovered the air base and bombed it, knocking it out for some weeks.

In April the air field became operational again and another raid on Valona was carried out, sinking two additional merchant ships; on the same day, however, German forces launched their invasion of Greece, and the base at Paramythia was bombed by the Luftwaffe and permanently destroyed.

The invading Axis powers (Nazi Germany, Fascist Italy and Hungary) occupied and dismembered the Kingdom of Yugoslavia.

When Germany and Italy attacked Yugoslavia on 6 April 1941, the Yugoslav Royal Navy had available three destroyers, two submarines and 10 MTBs as the most effective units of the fleet.

On 9 April, one Dornier Do 22K floatplane notably took on an Italian convoy of 12 steamers with an escort of eight destroyers crossing the Adriatic during the day, attacking single-handed in the face of intense AA fire.

On 26 October, the Yugoslav Partisans' Navy was organized first into four, and later into six Maritime Coastal Sectors (Pomorsko Obalni Sektor, POS).

Between June 1940 and September 1943, only 0,6 % of the personnel and 0,3 % of the supplies shipped from Italy to Albania and Greece were lost; two-thirds of these losses were caused by submarines, mostly British.

[10] British surface ships re-entered the Adriatic after the September 1943 armistice, when the much weaker Kriegsmarine forces remained the only opponent.

Since an Allied landing in the area was anticipated, OZAK also hosted a substantial German military contingent, the Befehlshaber Operationszone Adriatisches Küstenland commanded by General der Gebirgstruppe Ludwig Kübler.

Gradually the German navy was built up, mostly with former Italian ships found in an advanced phase of construction in the yards of Fiume and Trieste.

Starting in late 1943, the Allies undertook a major evacuation of civilian population from Dalmatia fleeing the German occupation, and in 1944 moved them to the El Shatt refugee camp in Egypt.

The Yugoslavs used the units in the British navy to transport materials and men, but especially to make landings on the islands of Dalmatia to liberate them from German occupation.

One notable action was the Battle off Ist on 29 February 1944 where a German convoy force of two corvettes and two torpedo boats escorting a freighter supported by three minesweepers.

The biggest engagement happened on 1 November, when two Hunt-class destroyers HMS Avon Vale and Wheatland were patrolling the coastal shipping routes south of Lussino.

On 14 December, HMS Aldenham became the last British destroyer lost in World Warr II when struck a mine around the island of Škrda.

[15] To prevent entrance to the North Adriatic in the last two years of World War II, Germany spread thousands of mines and blocked all ports and canals.

Nevertheless, the bluff worked since Hitler eventually awaited an allied landing in the northern Adriatic, and diverted important resources to the area.

It was only partially executed since the partisan Navy Commander in Chief, Josip Černi, refused to give his troops for the landing operation.

[19] Instead, a group of destroyers and MTBs shelled the German gun positions and 36 South African Air Force Bristol Beaufighters attacked the naval base installations with RP-3 3 in (76 mm) Rocket Projectiles.

[22] The very last operations of the German navy involved the evacuation of troops and personnel from Istria and Trieste before the advancing Yugoslavs that took place in May 1945.

The area is a huge sand spit running out into a big lagoon, and at its southern end the Tagliamento River enters the sea.