The ideas of an obscure Italian naval architect ignited an arms race that involved the world’s great and not so great naval powers.

The early 1900s was a dynamic era in the annals of naval warfare. When Fred T. Jane’s respected an­nual, Fighting Ships, published an article in 1903 by Italian naval architect General Vittorio M. Cuniberti describ­ing an innovative battleship design, naval thinking was energized around the globe.

The new design would ostensibly change forever the capabilities of such vessels. His concept was controversial, but Cuniberti was not a mere academ­ic dreamer. He was chief constructor for the Italian navy, and his designs had already been tested in four light battleships of the Vittorio Emanuele class.

Cuniberti urged that all-big-gun battleships be built with numerous 12-inch guns and reduced sec­ondary batteries, accompanied by 12-inch armor to withstand enemy fire. He argued for an abun­dant ammunition supply and high speed, superior to that of any battle­ ship then afloat.

Navy departments with little to lose in terms of obsolescent vessels, such as those in Washington and Tokyo, embraced the concept. But many senior officers who had begun their careers under mast and sail were less enthusiastic, as was the French Min­istry of Marine. Two years later, however, one pivotal incident swung the tide of naval opinion firmly behind the controversial theories advanced by Cuniberti.

That was the May 1905 Battle of Tsushima Strait, in which the fledgling Japanese navy nearly annihilated the opposing Russian fleet. The battle was, up to that time, the most significant exchange of gunfire between relatively modern battleships, and it provided telling evidence that Cuniberti’s revo­lutionary ideas were sound. Based on combat experience gleaned from that crucial battle, both Russian and Japanese naval architects concluded that the 12-inch gun was the minimal weapon likely to prove decisive in future fleet actions. They argued that smaller ­ caliber guns used space and personnel that could be better allocated for bigger guns. Japan promptly began construc­tion on its first modern all-big-gun battleship, while Russia soon invited Cuniberti to design a similar warship.

In the early 1900s, of course, it was Britain’s Royal Navy that reigned as the world’s most powerful fleet. Ac­cordingly, many of the leading rival naval powers anxiously watched to see whether the British Admiralty would exploit Cuniberti’s ideas. They did not have long to wait. First Sea Lord Admiral Sir John A. Fisher became an ar­dent exponent of the all-big-gun bat­tleship, and he used his formidable resolution and drive to design and pro­cure such vessels for the Royal Navy.

Fisher’s design encompassed two features beyond those advocated in print by Cuniberti. First, increased compartmentalization and solid, un­pierced bulkheads would enhance the new vessels’ survival probability. Sec­ond, revolutionary steam turbines would replace noisy, heavy, inefficient reciprocating steam engines.

Less than one year after Fisher took office, the first innovative British battleship, Dread­nought, was laid down at Portsmouth. Thanks to Fisher’s determined efforts, the ship was launched only 100 days later. She was commissioned in 1906 and immediately became the paragon for early 20th-century battleships and the most feared naval weapon at sea.

Dreadnought made every other exist­ing battleship obsolete, and her name became generic for similar fast, mod ­ern vessels. All battleships laid down before her were pejoratively labeled “pre-dreadnought.”

Meanwhile, Britain’s political rival on the Continent, Germany, was also pushing to establish a naval force of global stature. Admiral Alfred von Tirpitz had become state secretary of the Imperial Navy Office in 1897, and by 1902 he made evident his intention of transforming the German navy, formerly perceived as a coastal defense force, into the world’s second most powerful blue-water fleet.

The German Reichstag had autho­rized a buildup to 38 battle­ ships, including reserves, when details of Dreadnought‘s awesome firepower and armament reached Germany. Tir­pitz promptly suspended construction on Germany’s first competitive battle­ship, SMS Nassau, until she could be modified into a more formidable opponent. For Tirpitz and his supporters in Germany, the only possible response to Dreadnought was to imitate, then excel; concession of superiority was un­acceptable. Thus began a naval arms race for battleship superiority that con­tinued until the beginning of World War I. But Germany and Britain were not the only participants.

By 1907 the great power rivalry in Europe had resulted in a web of al­liances. The Triple Entente of Russia, France, and Britain stood opposed to the Central Powers of Germany, Italy, and Austria-Hungary. Both sides pushed to expand their military might. And the dreadnought construction race was an inherent part of preparation for war. All six powers comprising the two European military alliances constructed dreadnoughts, including four built and operated by Austria-Hungary.

Although never regarded as a great naval power, the Austro-Hungarian Empire encompassed much of the east­ern shore of the Adriatic Sea, ranging more than 250 miles along the Dalmat­ian coast from Trieste to Kotor. The main Austro-Hungarian naval base was located at Pula, while subsidiary bases with useful docking facilities were at Trieste and Rijeka. Farther to the southeast were fleet anchorages at Zadar, Split, Dubrovnik, and Kotor, the latter being one of the best in the Adri­atic Sea.

The four Austro-Hungarian dreadnoughts were designed in 1909. Con­struction of the first three, all of which were built in private Austrian shipyards, began the following year.

In order to induce the Hungarian parliament to approve the 1910 Austro­-Hungarian naval budget, the fourth battleship, christened Szent Istvan (Holy Stephen), was laid down in a small littoral region of Hungary, at a shipyard near Rijeka.

The first Austro-Hungarian dread­nought was put into service in 1912. Named Viribus Unitis (With United Strength) after the personal motto of the emperor, she was followed by sister ships Tegetthoff and Prinz Eugen. In 1915 Szent Istvan was commissioned, the last of the four dreadnoughts of the Tegetthoff class.

These vessels were modern battle­ships. They each carried 12 guns in four triple turrets, located two forward and two aft. Overall length was 498 feet, and the ships displaced 20,000 tons. Like Britain’s Dread­nought, the new Austro-Hungarian battleships were powered by steam turbines instead of reciprocating steam engines. There were four of these turbines in each vessel, produc­ing 25,000 shaft horse­power and generating a speed of 20 knots. The four Austro-Hungarian dreadnoughts of the Tegetthoff class were formidable warships, a quartet that created a potentially powerful foe for Triple Entente naval vessels in the Adriatic and Mediterranean.

But geography and lack of initiative on the part of the Austro-Hung arian naval staff limited the effectiveness of the four dreadnoughts. The empire’s principal naval base was at Pula, near the north end of the Adriatic Sea. Until Italy reversed its previous alliance with the Central Powers and declared war on Austria-Hungary in May 191 5, there were few worthwhile targets for the battleships in the Adriatic or its sur­rounding littoral area. In addition, Triple Entente forces, now expanded in number and known as the Allies, built a strong barrier across the Strait of Otranto, using permanent nets, minefields, and patrolling trawlers to stop Austro-Hungarian and German submarines from breaking out into the Mediterranean Sea.

As a result, the empire’s four dread­noughts spent most of their wartime lives moored to buoys inside Pula Har­bor. Limited sorties were conducted for gunnery practice or torpedo firings normally less than one hour’s steaming from their moorings. Fear that the battle­ships would be damaged by mines, torpedoes, or air attack seriously limited their employ­ment in bombardments of Italian coastal cities. These bombardments against Rimini, Ancona, Bari, and other Italian ports were conducted almost daily for several months by smaller Austro-Hungarian vessels after Italy entered the war. But the stationing of six British B-class submarines at Venice in October 1915 essentially curtailed the Austro­ Hungarian bombardments for the remainder of hostilities.

The upshot of all this was that the four Austro-Hungarian dreadnoughts spent a dispro­portionate amount of time sitting idle. For example, the log of Szent Istvan reveals she spent nearly 95% of her days idle at buoy 33.

Such inactivity undoubtedly proved boring to the dreadnoughts’ crews and affected their morale. Perhaps more important, it suggests that the battle­ ships and their crews never became re­ally prepared for combat. Most likely their crews remained inexperienced in many aspects of fleet gunnery, tactics, and especially damage control. None had been confronted with actual battle damage or wartime emergencies threatening the safety of their ship.

But the relative inactivity of the four dreadnoughts ended following a change in leadership at imperial naval head­ quarters. In February 1918, Nicholas Horthy, then commanding officer of Prinz Eugen, was promoted to rear ad­miral and made commander in chief of the Austro-Hungarian Adriatic Fleet. Based on his experiences aboard Prinz Eugen, Horthy realized morale of dreadnought crews was low, primarily due to their inactivity.

He resolved to correct this situation and restore discipline to the fleet by taking his ships to sea with the objec­tive of breaking the Allied barrier at Otranto. Such an assault would also partially avenge previous losses of Austro-Hungarian and German sub­marines to Allied forces there.

After several months of planning, Horthy and his staff conceived a sur­prise attack on the Strait of Otranto barrier by Austro-Hungarian cruisers and destroyers. His four dreadnoughts would provide support for withdrawal by engaging enemy ships that might come out in opposition from Valona or Brindisi. All imperial naval forces were to be in position for the assault by dawn on June 11, 1918.

According to Horthy’s plan, the four battleships would sortie from Pula in two separate groups. The first would be led by flagship Viribus Unitis, with Horthy and his staff aboard accompa­nied by a selected group of journalists. Prinz Eugen would be the second dread­nought in the first group, which sortied from Pula on June 8 under the pretext of going out for gunnery practice.

Viribus Unitis, Prinz Eugen, and their assigned escorts anchored in a remote bay during the daylight hours of June 9 and proceeded the following night to a fjord north of Dubrovnik. The remaining two dreadnoughts, Szent Istvan and Tegetthoff, sortied from Pula at 10:15 on the night of June 9, accompanied by one destroyer and six torpedo boats. This force was delayed by the unplanned late opening of the Pula harbor defense barrier and overheating of the starboard main turbine bracket in Szent Istvan. The two dread­noughts were thus about 90 minutes behind schedule when they encountered unex­pected Italian opposition in the Adriatic Sea.

The hostile Italian naval force was comprised of only two small torpedo boats, MAS (Motoscafo antisommergibili) 15 and MAS 21, and a unit led by Commander Luigi Rizzo aboard MAS 15. Rizzo was a colorful officer with a some­ what checkered career.

In December 1917 he had led a pair of MAS boats into a pro­tected harbor near Trieste, where they torpedoed and sank the old Austro-Hungarian coast-defense battleship Wien.

For this successful attack, Rizzo was awarded the Gold Medal and Knights Cross of the Order of the Military Ser­vice. Only four months later, however, Rizzo was imprisoned for seven days because he failed to take sufficient pre­cautions to protect his base at Ancona against enemy attack, even though an Austro-Hungarian landing detachment was reported to be in the vicinity. It seems logical to assume that former naval hero Rizzo was anxious to restore his good name when he set out to sea with his two MAS boats on the night of June 9, 1918.

The typical modus operandi for the short-range Italian MAS boats was to be towed to their operating area after dark by destroyers or torpedo (OS) boats, at which point they were cast free to begin their patrol. Before dawn, they would again rendezvous with their towing ves­sels and return to port.

On the night of June 9, Rizzo’s two MAS vessels were towed by torpedo boats 18 OS and 15 OS to Dalmatian coast’s inland waters, near the customary Austro-Hungarian shipping lanes from Rijeka to Kotor. But the MAS boats sighted no worthwhile targets, and they proceeded back to the prearranged ren­dezvous with their towboats, which they were scheduled to reach before sunrise at 4:17.

At 3:15, lookouts aboard Rizzo’s MAS boats spotted smoke off their starboard rear. Rizzo reversed course and ap­proached the potential target, which proved to be the dreadnought force of Szent Istvan, Tegetthoff, and their accompanying escorts. Without delay, Rizzo penetrated the Austro-Hungarian torpedo boat screen and attacked the first dreadnought in column. At 3:25, MAS 15 fired two torpedoes at a range of about 800 meters toward the un identified battleship, which was Szent Istvan.

Concurrently, MAS 21 attacked Tegetthoff, but her torpedoes failed. Szent Istvan was not so fortunate. Both Italian torpedoes exploded against her hull, starboard side amidships. Her after boiler room quickly filled with water, and the dreadnought took on a 10-degree list to starboard. 

Meanwhile Tegetthoff left formation to port and commenced zigzagging, presuming Szent Istvan had been tor­pedoed by a submarine. In the ensuing chaos, the two attacking Italian MAS boats evaded pursuing Austro-Hungari­an torpedo boat TB 76 by dropping depth charges in their wake.

Both MAS boats escaped and were towed back to their base at Ancona. For this exploit, Rizzo was awarded his sec­ond Gold Medal and Knight’s Cross of the Order of the Military Service. His proud countrymen later put his famous MAS 15 on display at the Museo di Risorgimento in Rome.

Meanwhile, conditions aboard Szent Istvan degenerated. Because of poor riveting, her transverse bulkheads could not stand the strain created by flooding, and rivets popped from their holes like bullets. Szent Istvan stopped so that steam from the forward boiler room could be supplied to her pumps, which theoretically could discharge 6,000 tons of water per hour out of the hull.

Shortly thereafter, however, the for­ward boiler room also partially filled with seawater, as did one ammunition magazine. Counter flooding was at­ tempted, and the dreadnought trained her entire main battery to port in a fu­ tile attempt to reduce her increasing starboard list.

At 4:45, Tegetthoff approached to take her stricken sister ship in tow, without success. The rising water in Szent Istvan’s forward boiler room soon extinguished all boilers except the two outboard to port. This incapacitated the pumps and left only enough elec­tricity for lighting purposes.

Attempts by her crew to patch the torpedo damage failed. The combined effects of increased flooding, lack of power for the water discharge pumps, and structural weakness of bulkhead riveting caused the sequential collapse of supposedly watertight transverse bulkheads. When the starboard list in­creased to such an extent that hatches for the secondary battery were submerged, the order was given to abandon ship. At 6:05, less than three hours after being struck by the Italian torpe­does, Szent Istvan rolled over to starboard and briefly floated upside down in the sea. With hundreds of her crew in the water nearby or attempting to scramble up on her inverted hull, the crippled dreadnought sank at 6:12.

Fortunately, escort vessels rescued 1,005 of her crew from the calm seas, but 89 men died as a result of the sinking. A motion-picture team and an officer aboard nearby Tegetthofboth took extensive film footage of the list­ing and sinking of Szent Istvan. The film was later spliced together, sold commercially, and widely shown around the world after the war.

When he received word of the tor­pedoing of Szent Istvan, Admiral Hor­thy realized immediately that his force had lost any chance of making a surprise attack on the Otranto barrier. He therefore ordered an immediate return to Pula.

Back in port, the Austro-Hungarians suspected that the Italians had probably been alerted to the supposedly top-secret plans for the attack on the Otranto barrier. In retrospect, however, those suspicions are difficult to confirm. No evidence has ever been produced regarding broken Austro-Hungarian codes or other successful Italian intelligence gather­ing. And the unplanned delays experi­enced by Szent Istvan placed her far behind her expected position when she was attacked.

Given the primitive command, con­trol, and communications possessed by the tiny Italian MAS boats, it seems highly unlikely that Rizzo’s small force could have been pinpointed, much less prepositioned itself, for the attack. Fi­nally, Rizzo makes no claim in his memoirs that the Italians had advance knowledge of Szent Istvan’s advance. Thus, it seems that it was merely luck that allowed the dreadnought to be lo­cated and sunk.

But Szent Istvan was not the sole representative of the four Austro­-Hungarian dreadnoughts to reach a grisly end. Flagship Viribus Unitis was soon to follow.

By September 1918, the Austro­ Hungarian empire was disintegrating . That month the Hungarian parliament demanded a recall of all national troops for defense of the homeland. Austro-Hungarian ground forces evacu­ated Albania the next month. In early October, a Southern Slav National Council was formed to lead a new Yugoslavian state that would encom­pass the entire Dalmatian coast, there by cutting off Austria-Hungary’s access to the Adriatic Sea.

As his empire splintered under na­tionalist centrifugal forces, Emperor Charles sued for peace in late October. On October 28, 1918, Admiral Horthy was ordered to turn over his entire fleet to the newly created National Council of Slovenes, Croats, and Serbs, which he did aboard Viribus Unitis, moored to its buoy at Pula, on October 31.

Horthy left his command that day, as did many of the officers stationed aboard Viribus Unitis, together with most Austrian and Hungarian crew members. Although Horthy left his flag captain, Croat Janko Vukovic, in com­mand of Viribus Unitis, the dread­nought was now manned primarily by an inexperienced crew of Yugoslavian sailors, unprepared to defend their ship. With the end of the war clearly immi­nent, harbor defenses at Pula were ei­ther relaxed or nonexistent.

But the Italian navy was unaware of the transition within Pula Harbor. Early the following morning, two young Italian naval officers, Raffaele Rossetti and Raffaele Paolucci, approached the lax defenses of Pula Harbor riding a new underwater weapon-a veritable human torpedo called Mignatta. Built from a salvaged and redesigned German torpedo, it was loaded with two limpet mines carrying 200 kilograms of explosives apiece in place of its origi­nal warhead. Powered by a compressed air engine, Mignatta successfully pene­trated the now lax barrier around Pula Harbor and steamed quietly toward the moored Viribus Unitis, which was fully illuminated and had many of her water­ tight doors open.

The two daring Italian attackers suc­ceeded in attaching their mines be­ neath the hull of the unsuspecting dreadnought. Before they could effect their escape, however, Rossetti and Paolucci were spotted by a petty officer aboard Viribus Unitis, who pursued and captured them in a small boat.

Upon being brought aboard the for­mer Austro-Hungarian dreadnought, the two Italian officers demanded to speak to Captain Vukovic, and they warned him that mines had been at­tached to his ship and would detonate in about 15 minutes. Acting prudently, Vukovic gave the immediate order to abandon ship, but many of the sailors among his green crew panicked, and near chaos ensued aboard Viribus Unitis as lifeboats were hastily lowered into the water.

Meanwhile, Captain Vukovic ascended to the bridge and awaited the explosion, which occurred on schedule. At 6:30, both mines exploded, and Viribus Unitis sank within 15 minutes. Nearly 400 crew members died in the sinking, including Captain Vukovic, who chose to go down with his ship.

Thus two of the four Austro-Hungarian dreadnoughts were sunk as a result of daring combat assaults by the Italian navy. The remaining two survivors, Tegetthoff and Prinz Eugen, also had short lives.

After the treaties were signed that ended World War I, Prinz Eugen was ceded to France and steamed to Toulon. There she was stripped of her main bat­tery guns and other salvageable equip­ment. In early 1922, the hulk of the once formidable Austro-Hungarian dreadnought was towed into the Mediterranean Sea and sunk after being used as a floating target ship by the French battleships France and Bretagne.

Tegetthoff had an even more prosaic demise. Transferred to Italy via the peace treaty, she was scrapped at La Spezia in 1925. Meanwhile, the sunken wreck of Viribus Unitis was broken up in the harbor of Pula before 1930.

Szent Istvan reappeared briefly in the news during 1975, nearly 57 years after her sinking. A Yugoslavian navy diving team located the wreck that year and filmed video footage later shown on Serbian television. The sunken dreadnought was also filmed by an Ital­ian television crew three months later. In later years, Hungarian, Austrian, and Croatian teams all dived on the hulk.

Szent Istvan remains an irresistible magnet for divers, although exploration of the dreadnought is fraught with peril. The wreck is located in nearly 65 meters of water. At that depth, exploration time on site, even for skilled scuba divers, is normally only about 12 to 15 minutes. While the lure of souvenirs remains strong, many today feel that the wrecks should be left intact.

In retrospect, the four Austro­-Hungarian dreadnoughts were relatively impotent as weapons of war during their short lives. But, in a larger sense, they epitomized the disappointing im­pact of this class of vessels on naval warfare . Although the commissioning of HMS Dreadnought in 1906 sparked a worldwide naval arms race, and the ships themselves became the most sig­nificant measure of a nation’s maritime strength, dreadnoughts rarely lived up to their proponents’ claims that they would be the major element of sea power. For example, neither Britain’s Dreadnought nor Germany’s Nassau played a major role in World War I. Dreadnought missed the Battle of Jut­land in 1916, was sold for less than 3 percent of her original cost in 1921, and scrapped two years later. Although Nas­sau rammed a Royal Navy destroyer at Jutland, she was ceded to Japan at the end of the war and scrapped in 1920.

As the short lives of the four Teget­thoff-class ships tend to suggest, rarely did the money, materiel, and personnel expenses of dreadnoughts justify the massive expenditures made on them. They were, in essence, exemplars of a futile naval arms race.

WILLIAM H. LANGENBERG is a retired rear admiral in the U.S. Naval Reserve and frequently writes on naval matters.

This article originally appeared in the Winter 1999 issue (Vol. 11, No. 2) of MHQ—The Quarterly Journal of Military History with the headline: Rise and Fall of the Dreadnaught

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