The Austro-Hungarian Navy was the sixth strongest in the world on the eve of the Great War. The development of the fleet gained momentum from the late 1860s. The Monarchy could not very well kick the ball next to the English or French fleet in the world seas. However, after the unification of Italy, it felt its own coastline in danger. The match unfolded for dominance of the Adria. The first clash soon took place, culminating in the victory of the Monarchy on the Dalmatian coast at the island of Lissa in the War of 1866.
After that, the two countries competed with each other to develop their fleets. They were essentially in balance, one occasionally overtaking the other with a new class of ships. The culmination of the Monarchy’s developments was the four battleships of the Tegetthoff class, which surpassed the Italian battleships of the time in firepower. But the Italian response was not left out either. Practically at the same time, they built their battleship Dante Alighieri, of the same strength as the monarchical dreadnought.
In the naval warfare of the Great War, the Adriatic theatre remained unimportant. The Entente was content to blockade the units of the Monarchy with a sea lock. Thus, the fleet of the Monarchy could only be used for limited purposes. Such was the case with the bombing of military installations and supply lines on the Italian coast on the first day after the Italian war declaration. Outside the Adriatic, only submarines playing the lockout could escape. You can read some details about this here.
The Navy of the Monarchy is presented with relatively few badges, most of which depict submarines. The general badge of the fleet is shown in this entry. Interestingly, the badge is not adorned with the image of a state-of-the-art ship, but a unit of a previously built obsoleting type, the Erzherzog class. For comparison only, the main artillery in this class had 4 24 cm cannons, while the ships in the Tegetthoff class had 12 30.5 cm cannons.
I also thought to discover a drawing of this type of ship on the postcard attached to the post. The card also signals the upcoming holiday to my dear readers. The attached photo depicts SMS Erzherzog Ferdinand Max.