The Adriatic Campaign of World War I was a naval campaign fought between the Central Powers and the Mediterranean squadrons of the Allies, specifically the United Kingdom, France, the Kingdom of Italy, Australia, and the United States.
Characteristics First World War naval action in the Adriatic Sea consisted mainly of Austro-Hungarian bombardments of Italy's eastern coast, and wider-ranging German and Austro-Hungarian submarine forays into the Mediterranean.
Allied forces mainly limited themselves to blockading the Central Powers' navies in the Adriatic, which was successful in regards to surface units, but failed for the U-boats, which found safe harbours and easy passage into and out of the area for the whole of the war.
Considered a relatively secondary part of the naval warfare of World War I, it nonetheless tied down significant forces.
The Adriatic campaign was also important because for the first time two new weapons were used successfully in warfare, viz. the MAS torpedo boat of Luigi Rizzo that sank the battleship and the human torpedo of Raffaele Rossetti that sank the battleship in 1918.
History 1914 Beginning of the war
On 6 August 1914 an Anglo-French naval agreement was signed, giving France leadership of naval operations in the Mediterranean. The remaining British Mediterranean forces – one armoured cruiser, four light cruisers, and 16 destroyers – were placed under the control of the French Mediterranean Fleet, and bases at both Gibraltar and Malta were opened to the French.
One day after the French declaration of war against Austria-Hungary on 11 August, a French fleet under Admiral Augustin Boué de Lapeyrère arrived at Malta. He had orders to sail with all available French and British ships, pass into the Adriatic Sea, and undertake whatever operations he thought best against Austrian ports. Lapeyrère decided to surprise Austrian vessels enforcing a blockade of Montenegro. The main Allied force comprised the French battleships and , and the cruiser . Two French squadrons of pre-dreadnought battleships, two squadrons of cruisers, and five destroyer squadrons were held back in support. The British support group comprised two armoured cruisers and three destroyer divisions. The Anglo-French force succeeded in cutting off and sinking the old Austro-Hungarian light cruiser off Bar on 16 August in the Battle of Antivari. However, Allied hopes of baiting the Austrian capital ships into an action were not realized.
Throughout most of late August most of the action was simple bombardment of Serbian and Montenegrin troops by Austrian ships. On 9 August, the pre-dreadnought shelled the French radio station at Budva, while the destroyer shelled Mount Lovćen. On 17 August, Monarch shelled a Montenegrin radio station off Bar, then another station off Volovica Point on 19 August. Meanwhile, a French squadron shelled Austrian troops on Prevlaka.
The French and Montenegrin forces attempted to cause havoc also at Cattaro in September, October and November 1914, and the Austro-Hungarian navy was called in there also, resulting in a decisive defeat for the Allies.
Both the French and the Austrians spent much of this time laying extensive minefields throughout the shallow waters of the Adriatic. Mostly this was done by destroyers, and at night. Several steamships ran afoul of these mines and either sank or were damaged.
The Goeben
In July, , a German battlecruiser, sailed to Triest from Pola. She and the German cruiser had been anchored there since the beginning of the summer. On 1 August, Goeben and Breslau rendezvoused at Brindisi, then headed for Messina to take on coal. They left for Constantinople on 6 August, shadowed by the British cruiser .
On 7 August, an Austro-Hungarian Fleet—consisting of six battleships, two cruisers, and 19 destroyers and torpedo boats—sortied from Pola to escort Goeben and Breslau through Austro-Hungarian territorial waters, returned to port following day without ever making contact. Goeben and Breslau briefly engaged HMS Gloucester and the chase was abandoned by the British. By 10 August, both German warships were safely in the Dardanelles and heading for Turkey.
Winter In November, the French submarine managed to slip into the Bocche di Cattaro as far as Topla Bay but was chased out by the Austrian destroyer , and the torpedo boat Tb 57T. In mid-December, the French submarine raided the harbour barrage of Pola to wait for her chance to intrude. Two days later, on 20 December, during an attempt to sneak into the harbour she got entangled in an anti-submarine net and could not free herself. Forced to surface for fresh air, she was sunk by the Austrian destroyer and Tb 63T, with three casualties. The Austrians raised the wreck between December 1914 and February 1915. It was then repaired and commissioned as in June 1915.
On 21 December, the submarine scored one torpedo hit on the French battleship Jean Bart off Sazan Island. The battleship had to withdraw to Malta for extensive repairs.
1915 In February, the French destroyer —while escorting the transport Whitehead to Bar—was sunk after hitting a mine. Also that month, the Austrian submarine U-12 was unsuccessfully attacked off Cape Mendra by a French submarine. Austrian destroyer shelled Montenegrin positions at Bar with Tb 15 and Tb 68F.
In April, the Austrian —commanded by Lt. Georg Ritter von Trapp—chased the French armoured cruiser off Paxos, but was unable to fire any torpedoes. U-5 also torpedoed the French armoured cruiser after a two-day chase off Santa Maria di Leuca, causing 684 fatalities including Rear-Admiral Sénès. Only 137 French sailors survived. The Austrian torpedoed and damaged the British light cruiser . Also, the Austrian destroyer shelled enemy positions at Bar.
Bombardment of Ancona
When Italy declared war on Austria-Hungary on 23 May, the Austrian fleet was quick to act, launching several attacks on the Marche region of Italy. That day, the destroyer Dinara and Tb 53T bombarded the port of Ancona. The destroyer —on reconnaissance duty between Palagruža and Cape Gargano—shelled the semaphore and radio station at Vieste and fired upon the Italian destroyer . On 24 May, the bulk of the Austrian fleet at Pola sailed for the Italian Adriatic coast. This included the dreadnoughts Viribus Unitis, , and eight semi and pre-dreadnoughts. The fleet bombarded several cities and other targets in and around the Province of Ancona, especially damaging the port and town of Ancona itself.
The destroyer shelled the Italian airship Città di Ferrara off Ancona. The semi-dreadnought and two torpedo boats bombarded Potenza Picena, then returned to Pola. The Radetzky-class semi-dreadnought , with two torpedo boats bombarded Senigallia, destroying a train and damaging a railway station and a bridge, then returned to Pola. The torpedo boat Tb 3 was unsuccessfully bombed by an Italian airship. The light cruiser shelled the Italian signal station at Cretaccio Island, while the armoured cruiser —with two torpedo boats—shelled Rimini, damaging and derailing a freight train. The destroyer shelled the signal station near Torre di Mileto. The light cruiser , a destroyer and two torpedo boats entered Corsini Channel and shelled an Italian torpedo boat station, a semaphore station, and coastal artillery batteries.
The light cruiser —aided by four destroyers—sank the Italian destroyer Turbine in a pitched battle south of Pelagosa. The destroyer shelled the railway embankment near Manfredonia while the destroyer shelled the Manfredonia railway station.
Finally, Austro-Hungarian flying boats dropped bombs on Venice and airship hangars at Chiaravalle.
Allied raids
Coincidentally with the Austro-Hungarian attack on Ancona, the Italian destroyer Zeffiro shelled and captured the Austro-Hungarian naval station and post at Porto Buso on the first hours of 24 May. Austro-Hungarian troops withdrew from the nearby town of Grado as a consequence.
On 5 June, four different Allied task forces attacked the Austrian coast. Four Italian armoured cruisers, escorted by four French destroyers, shelled Cavtat; the British cruiser Dublin—escorted by five Italian destroyers—shelled Donzella; the Italian light cruiser —escorted by four destroyers—bombarded Lastovo; the Italian light cruiser , two Italian and two French destroyers shelled the island of Lissa. On 9 June, a mixed force of British, French and Italian destroyers shelled the Austro-Hungarian signal station at Cape Rondini in Albania.
The summer of 1915 Sankt Georg and a squadron of torpedo boats bombarded Rimini on 16 June, causing minor damage. Then on 17 June, the cruisers Novara and Admiral Spaun and their escorts attacked and sank the Italian steamer Maria Grazia off Giulianova. The next day, they shelled Rimini and Fano, destroying the Italian signal station there.
The summer of 1915 was a successful time for Austrian submarines as well: on 10 June, sank the Italian submarine and torpedo boat ; sank the Italian torpedo boat PN 5 on June 26 off Venice; U-4 torpedoed and sank the on 18 July; and U-5 captured the Greek steamer Cefalonia off Durazzo on August 29. But this was not without losses. On 13 August, was sunk at Brindisi by the French destroyer Bisson, after having been severely damaged by the Italian auxiliary cruiser the day before.
The Austro-Hungarian naval air-arm also began regular bombing raids against Bari and Brindisi in June, slightly damaging the British protected cruiser in one such raid with machine gun fire. And the British armed trawler Schiehallion was sunk by a mine. The was sunk off Venice by the German submarine on July 2. While the Italian scout cruiser shelled Gravosa station on 18 July, the scout cruiser Quarto and three Italian destroyers attacked the Austrian installation at Guiparra.
SMS Helgoland, seven destroyers and four torpedo boats supported an Austrian landing at Pelagosa on 28 July. The landing was repulsed by the Italian garrison, that had arrived in the island on July 11. On August 17 the light cruisers "Helgoland", "Saida" and several destroyers bombarded the island again. The water reservoir was severely damaged and the next day the Italians began the evacuation. On 17 August, one of the cruisers was unsuccessfully torpedoed by an Italian submarine on return journey. The last act of the summer was the sinking on 26 September of the Italian battleship in Brindisi harbour by Italian-speaking Austro-Hungarian saboteurs. Over 450 were killed.
In late September, the Allies established the Otranto Barrage, an attempt to blockade the entrance to the Adriatic Sea at the Strait of Otranto.
December
In early December, the French submarine ran aground off the Bojana River estuary due to bad navigation, and was sunk by the Austrian destroyer . The cruiser Helgoland and three destroyers sortie against the Otranto Barrage from 5–22 December and performed reconnaissance off the Albanian coast and San Giovanni di Medua. They sank an Italian picket boat, three steamships loaded with ammunition and two armed schooners en route to Northern Albania.
The light cruiser SMS Helgoland and five Tatra-class destroyers left Cattaro and headed for Durazzo late on 28 December 1915. While on passage the French submarine was rammed by the cruiser SMS Helgoland, and finally sunk by gunfire from the destroyer . Early the next day, the Austrians squadron opened fire on Durazzo targets, sinking some small ships. Then they ran into a minefield. The destroyer Lika was sunk and Triglav was damaged. She was taken in tow and the Austrian force sailed slowly to north.