A naval arms race between the Austrian Empire and Italy began in the 1860s when both ordered a series of ironclad warships, steam-propelled vessels protected by iron or steel armor plates and far more powerful than all-wood ships of the line. These ships were constructed to establish control over the Adriatic Sea in the event of a conflict between the two countries.
The unification of much of Italy in this time period resulted in the amalgamation of the various navies of the former Italian states into the Regia Marina (Royal Navy). The Sardinian component included two ironclads, ordered from France in 1860, which became Italy's first broadside ironclads. The country quickly began a substantial construction program to bolster the Regia Marina, as the Italians believed that a strong navy would play a crucial role in making the recently unified kingdom a great power.
These actions captured the attention of the Austrian Empire, which viewed Italy with great suspicion and worry, as irredentist claims by Italian nationalists were directed at key Austrian territories such as Venice, Trentino, and Trieste. In response to the growing strength of Sardinia—soon to be Italy—the Imperial Austrian Navy ordered two ironclads in 1860. This began a naval arms race between Austria and Italy, centered around the construction and acquisition of ironclads. This continued for the next six years, and by the time the war broke out between the two in 1866, Austria possessed seven ironclads to Italy's twelve.
While Italy emerged on the winning side of the war and acquired the Kingdom of Lombardy–Venetia under the terms of the Treaty of Vienna, the Regia Marina was decisively defeated at the Battle of Lissa by the much smaller Imperial Austrian Navy. Their poor performance led to a period of neglect with reduced naval budgets and a halt to new ship construction; Italy would not have another ironclad laid down until 1873.
Meanwhile, Austria reformed itself into the Austro-Hungarian Empire in 1867 after losing the Seven Weeks War to Prussia. In the years following the Battle of Lissa, Wilhelm von Tegetthoff would oversee the construction of three additional ironclads and the rebuilding of a fourth. After Tegetthoff's death in 1871, the Austro-Hungarian Navy entered its own period of neglect, with just five additional ironclads being constructed in the ensuing thirteen years. Both navies engaged in further construction projects throughout the 1870s and early 1880s, but the arms race ended in the 1880s due to the signing of the Triple Alliance between Italy, Austria-Hungary, and Germany in 1882 and the introduction of new technologies that led to the development of pre-dreadnought battleships. Despite their alliance, however, Italy and Austria-Hungary would engage in a second naval arms race centered around the construction of battleships at the turn of the century. This arms race would continue until the beginning of World War I.
Background
Establishment of the Regia Marina
In March 1860, Camillo Benso, Count of Cavour became the Kingdom of Sardinia's naval minister. He assumed this role at a time when Sardinia was rapidly expanding into Northern and Central Italy. This expansion likewise resulted in the growth of the kingdom's navy. In April, Cavour oversaw the incorporation of Tuscany's small fleet into the Royal Sardinian Navy. Immediately after the Tuscan fleet had been integrated into the Sardinian navy, Cavour placed an order with the Société Nouvelle des Forges et Chantiers de la Méditerranée to construct two armored warships in Toulon. These two ships would become the Formidabile class, the first ironclads to serve in the Italian peninsula. While foreign powers such as Austria watched the growth of Sardinia and the expansion of its army closely, the consolidation of the Sardinian Navy after the incorporation of multiple states across the Italian peninsula received far less attention. This allowed Cavour to continue his work incorporating the various fleets Sardinia inherited as more and more Italian states joined the growing kingdom.
Garibaldi's conquest of the Kingdom of Two Sicilies marked the beginning of the Sardinian Navy's transformation into the Italian Regia Marina. When the Italian revolutionary landed in Sicily in May 1860, only two steamships were at the disposal of his thousand volunteers. By the time Garibaldi had conquered the island, he had more than 12 steam ships of various types which would later assist in transporting his army across the Strait of Messina to Southern Italy. These numbers were bolstered by the desertion of most of the Neapolitan Navy in July 1860 to Garibaldi's cause. Following Garibaldi's conquest of Naples in September, the remainder of the Neapolitan Navy was handed over to Carlo Pellion di Persano for incorporation into the Sardinia Navy.
The rest of Southern Italy fell in short order and in March 1861, the Kingdom of Italy was proclaimed. By this time, the vast majority of the former navies of the various Italian states had been brought into the Sardinian Navy. Two weeks after the establishment of the Kingdom of Italy, the Italian Regia Marina was created as a single unified naval force for the newly formed kingdom. Cavour immediately asked the Italian Chamber of Deputies for an unprecedented 20,000,000-lire budget to expand the Regia Marina beyond its newly acquired ships. The funds would also be used to construct additional ironclads as well as establish an Italian naval base at Ancona on the Adriatic Sea. The stage was thus set for the Italian ironclad program.
Development of the Imperial Austrian Navy: 1854–1860
Even before the unification of Italy, the Imperial Austrian Navy had been undergoing its own expansion ever since the promotion of Archduke Ferdinand Maximilian of Austria (the future Emperor Maximilian I of Mexico) to the office of Kontreadmiral (Rear Admiral) and to the post of Oberkommandant der Marine (Commander-in-Chief of the Navy) in September 1854. At the age of 22, Ferdinand Max became the youngest Oberkommandant in the history of the Imperial Austrian Navy, being a year younger than when Archduke Friedrich of Austria assumed command of the navy ten years earlier. Despite his age and his lack of experience in battle or command on the high seas, Ferdinand Max was described by naval historian Lawrence Sondhaus as "the most gifted leader the navy had ever had, or ever would have." Ferdinand Max worked hard to separate the Imperial Austrian Navy from its dependence upon the Imperial Austrian Army, which had nominal control over its affairs. As the younger brother to Franz Joseph I, Ferdinand Max was given great freedom by the Emperor to manage the navy as he saw fit, especially with respect to the construction and acquisition of new warships.
Ferdinand Max immediately went to work expanding the Imperial Austrian Navy. Fears of over-dependence upon foreign shipyards to supply Austrian warships enabled him to convince his brother to authorize the construction of a new drydock at Pola, and the expansion of existing shipyards in Trieste. Furthermore, Ferdinand Max initiated an ambitious construction program in the ports of Pola, Trieste, and Venice, the largest the Adriatic had seen since the Napoleonic Wars. By 1855, a screw-powered ship-of-the-line was under construction in Pola after failed bids with British and American shipbuilding firms, while two screw-frigates and two screw-corvettes were being built in Trieste and Venice respectively.
By the spring of 1855, the Imperial Austrian Navy consisted of four frigates, four corvettes, and two paddle steamers in active service in the Mediterranean Sea. This would be the largest Austrian fleet since before the War of Austrian Succession over 100 years prior. Despite these efforts however, the Imperial Austrian Navy was still considerably smaller than its French, British, or Italian counterparts. Indeed, the Imperial Austrian Navy was still attempting to catch up to the technological developments which had emerged during the first half of the 19th century with respect to steam power, when the emergence of the French iron-plated floating battery Dévastation gained international attention following its use during the Crimean War in October 1855. Dévastation would signal the beginning of the emergence of ironclad warships over the course of the next decade.
Following Austria's defeat during the Second War of Italian Independence, Ferdinand Max proposed an even larger naval construction program. This fleet would be large enough not only to show the Austrian flag around the world, but also to protect its merchant marine as well as thwart any Adriatic ambitions from the growing Kingdom of Italy. However, constitutional reforms in Austria after the military defeat, as well as the recent introduction of ironclads into the navies of the world, would make the proposal more expensive than initially intended. While the Archduke had previously had free rein over naval affairs, and had enjoyed an unprecedented funds to complete his various projects, Austria's financial difficulties in the immediate aftermath of the war stalled his plans. However the Italian ironclad program between 1860 and 1861, coupled with Austrian fears of an Italian invasion or seaborne landing directed against Venice, Trieste, Istria, and the Dalmatian Coast, demanded an Austrian naval response.
Onset of the Austro-Italian ironclad arms race Austrian reaction to the unification of Italy
When Giuseppe Garibaldi's conquest of the Kingdom of the Two Sicilies began in May 1860, the Austrian Empire responded by recalling its small fleet stationed in the Levant under the command of Fregattenkapitän (Captain) Wilhelm von Tegetthoff. Kontreadmiral (Rear Admiral) Bernhard von Wüllerstorf-Urbair then deployed the Imperial Austrian Navy to the waters off of Naples in order to prevent Garibaldi from attacking the city by sea. However, the defection of the Neapolitan Navy and Garibaldi's rapid advance up the Italian Peninsula after making landfall at Calabria rendered this fleet useless. The Austrian fleet was instead tasked with transporting King Francis II from Naples to Gaeta.
The collapse of the Kingdom of the Two Sicilies in just a matter of months sparked a diplomatic and military crisis in Vienna. While Garibaldi finished his conquests, the Sardinian Army invaded the Papal States and the growing Sardinian Navy entered the Adriatic to blockade the port of Ancona. The Austrian Empire viewed Sardinian warships in the Adriatic as an overtly hostile act, and fears of Garibaldi continuing his military campaigns by attempting a landing in Istria or the Dalmatian Coast resulted in even greater alarm. The Austrian government knew these lands were deemed Italia irredenta (Unredeemed Italy) by revolutionaries such as Garibaldi, due to their historical ties with the former Venetian Republic. To make matters worse, Garibaldi had several hundred Hungarian volunteers in the ranks of his army. Vienna calculated that should a landing along the Austrian coastline by Garibaldi be successful, the whole southern and eastern portions of the country could potentially erupt into revolution, much like the revolutions in 1848 which nearly toppled the Austrian Empire altogether.