On 23rd of May 1915, Italy declared war on the Austro-Hungarian Empire. When the decision was made, the Italian Army was in a poor state and based on their agreement with the Entente powers, they were expecting that Britain and France would do all the fighting that was necessary. On the other hand the Italian treasury could not fund a war, but again there were promises of money and munitions from London and Paris.
With all this promises and hopes Italy entered the was, and this decision to turn against they ally and enter the war surprised many. For example the Austro-Hungarian and German Leadership, the Italian Army, treasury and Navy. When the declaration of war was submitted, literally no one was prepared to fight a war, especially Italy.
At this time Austria-Hungary was already fighting a war with more or less success for over a year, and their Navy was already in a combat ready status. So when the Italians declared war, the Austro-Hungarian Navy was quick to react, they literally pulled together a task force to deliver some painful punches to the Italians, whom at this point were still trying to figure out what to do now that they declared a war on the Empire. I know it sounds weird and maybe unbelievable but this was literally the case. The Italian Navy was not in a state to fight a war at this point as they were not informed on time that they should.
So Italy declared war on the 23rd of May 1915, and on the same day, the Austro-Hungarian Navy already sent their units in to the Italian side of the Adriatic Sea to poke the Italians. The destroyer SMS Dinara and torpedo boat Tb-53T bombarded the port of Ancona. The destroyer SMS Lika, was sent on a reconnaissance mission between Palagruža and Cape Gargano and if she was already there, also shelled the semaphore and radio station at Vieste. The Italians only could send one destroyer to defend the area which was the Turbine. A small duel started between the opposing forces with Lika coming out as a winner from the battle, damaging the Italian destroyer.
But they did not stop here. On the Next day, 24th of May the Navy organised few task forces to hit the Italians and the Admiralty made a risky move which was unseen from them before. They pulled together the majority of the Navy for a Raid. Almost the whole fleet lined up and left Pola to attack the Italian Coastline. The ships that were operating in enemy waters were also redirected to join them. The fleet consisted of 3 dreadnoughts, 8 pre-dreadnoughts, 2 scout-cruisers, and around 20 destroyers and torpedo boats.
We can safely say that the attack surprised the Italians. And i wan to really emphasise on this. No-one was expecting the Austro-Hungarian Navy to pull off a such a large scale operation in literally a minute notice.
SMS Tegetthoff and the destroyer SMS Velebit shelled the Italian airship Città di Ferrara off Ancona. The SMS Radetzky and two torpedo boats bombarded Potenza Picena, then returned to Pola naval base. The SMS ZrÃnyi joined by two more torpedo boats bombarded Senigallia, destroying a train and damaging a railway station and a bridge, before returning home. The torpedo boat TB-3 was attacked by an Italian flying-boat but this was unsuccessful.
Another Task force led by the scout cruiser SMS Admiral Spaun bombarded the Italian signal station at Cretaccio Island, while SMS Sankt Georg supported by two torpedo boats shelled Rimini, damaging a freight train. In the meantime the destroyer SMS Streiter attacked the signal station near Torre di Mileto. The light cruiser SMS Novara, a destroyer and two torpedo boats entered Corsini Channel and shelled an Italian torpedo boat station, another semaphore station, and few batteries of coastal artillery.
Parallel to this another task force consisted of the scout cruiser SMS Helgoland and four destroyers ran into the Italian destroyer Turbine which earlier had an encounter with the SMS Lika and got in a fight south of Pelagosa.
The destroyer SMS Tátra shelled the railway embankment near Manfredonia while the destroyer SMS Csepel shelled the Manfredonia railway station. But not only the Navy took part of this raid. The Austro-Hungarian Air force also got involved and sent their flying boats to bomb on Venice and the seaplane hangars at Chiaravalle.
As the Aftermath of this raid was significant. The bombed railway stations and signalling stations pushed back the mobilisation of the Italian army with weeks if not months. This raid also showed the real combat capability of the Austro-Hungarian Navy which had to be taken in to consideration going forward. As a result, a large Allied blockade was raised to prevent the Austro-Hungarian fleet from leaving the Adriatic Sea. The "Otranto Barrage" would be raided by the Austro-Hungarian Navy several times throughout the war, but the Austro-Hungarian warships rarely left the bases after this raid. Which is very disappointing knowing what they can and did achieve if they are sent in to a fight.
Unfortunately this has not happened and after this raid most of these ships spent the rest of the war in ports.
