Italy enters World War I
Italy goes to war against Austria-Hungary
23 May - 2 December 1915
author Paul Boșcu, January 2017
Italy entered the Great War on the side of the Entente in order to gain the Trentino and Trieste areas from Austria-Hungary. The first battle proved to be a brutal test for the Italian Army as it attacked strong Austrian defensive potions across the Isonzo river, with minimal gains.
Italy entered the Great War on the side of the Entente, with the goal of gaining the Trentino and Trieste areas from Austria-Hungary. The existence of fixed defenses on both sides dictated that from the outset the campaign would be mainly static. In murderous fighting, the Italians managed briefly to capture key tactical positions on the Isonzo Front, like Monte San Michele overlooking Gorizia, only to be thrown off them again by determined Austrian counterattacks. Eventually December brought mutual exhaustion, and the fighting petered out as both sides tried to cope with the freezing cold of winter in the mountains.

At the end of 1914 Italy was being courted by both the Central Powers and the Allies. The Italian government had prudently declared neutrality, despite the implications of the Triple Alliance that should have taken Italy into the war on the side of Germany and Austria. Her army and navy were the most powerful of the neutrals in Europe. Her geographical position was strategically important, lying on the flanks of both the Central Powers and the Allies. Italy had the naval power to control the Mediterranean sea lanes, notably in the Sicilian Narrows, where a combined Austro-Italian navy could have denied access to the Suez Canal.

The Austro-Italian frontier had been created artificially by a treaty in 1866 engineered by Otto von Bismarck, providing Austria with a barrier of mountains from which her army could sweep down at will onto the north Italian Plain. Any Italian offensive would have to be conducted uphill. Italy's difficulties were increased by the shape of the frontier, a giant 'S' on its side, with a huge salient projecting into Italy in the Trentino district, and the Udine salient extending into Austrian territory. Of these the Trentino was potentially the more dangerous, but its poor road and rail communications also presented problems to Austria's military planners.

The Italians planned to attack on the Isonzo front, where the objectives of Trieste and the route to Vienna lay within reach, along with the tempting opportunity to link up with the armies of Serbia and Russia. The Italian Achilles heel was the Trentino front. There, a successful Austrian breakthrough would isolate the Italian armies on the Isonzo. The layout of the Italian railway system in the region acknowledged this: a double-track route ran parallel to the frontier, with spurs branching off up the valleys.

Before the war, Italy was allied with the Central Powers. On the outbreak of war in August 1914, the Italians reneged their commitments, claiming that the aggressive nature of the actions taken by the Central Powers breached the defensive nature of the original treaty agreements. An alliance containing Austria-Hungary was never likely to sit well with an Italian population, who still harbored a grudge against the Austrians over disputed territories, particularly focussed on the Trentino and Trieste areas.

There was a popular groundswell headed by a nationalist movement, Italia Irredenta (Unredeemed Italy), that Trentino and Trieste should be returned to Italy, thereby finally uniting the Italian population. This stance conveniently omitted consideration of the interests of the many Germans and Slavs who had also made their home in these lands.

The majority of Italians, people and parliamentarians alike, had no enthusiasm for the dangerous adventure. The impetus came from Prime Minister Antonio Salandra, Foreign Minister Sidney Sonnino, King Victor Emmanuel III, and a collection of political and cultural revolutionaries.

Once it became evident that Italy was not entering the war on the German side, there was a rush by British and French diplomats to secure the Italians to augment the ranks of the Entente. These efforts culminated in the secret Treaty of London under the provisions of which Italy would declare war on the Central Powers in return for promises of gains in the disputed provinces in the Tyrol and the Austrian Littoral which included the port of Trieste. Agreements were also hammered out over the division of the spoils with Serbia along the Dalmatian coastline of the Adriatic. In consequence, Italy declared war on Austria-Hungary.

The Italians opened up a new front stretching for some 400 miles along the border Italy shared with Austria-Hungary. The frontier formed the shape of a huge ‘S’, with the Trentino Salient bulging into Italy and the Udine pushing into Austria. Most of the front was extremely mountainous in character and could be divided into three sectors: the Trent Front around the Trentino Salient; the Alpine Front; and finally the thirty miles of the Isonzo River sector running down to the Adriatic, although even here the ground was dominated by a series of hills and ridges.

The configuration of the border gave the Italians a significant strategic conundrum. If they were to attack on the Isonzo Front, where the terrain offered the best chance of progress, they would be vulnerable to a devastating Austrian attack coming from the Trent Front, which was effectively behind the Italian lines, and which would threaten to cut off both the Alpine and Isonzo Fronts.

The Italian Army was large, consisting of some 850,000 soldiers, and based on a conscription system, but there were severe problems with both equipment and training. The officers were still recruited from a fairly narrow regional base and there was an inherent lack of professionalism in their general approach. Although King Victor Emmanuel III was nominally Commander-in-Chief, the Italian Chief of General Staff and de facto commander was General Luigi Cadorna.

Cadorna had demonstrated considerable abilities as an administrative staff officer and was widely respected as a theoretical military strategist, although he had no relevant experience as a field commander. The lower ranks of his army were largely drawn from peasant stock and were dogged by high levels of illiteracy, which hampered the development of good NCOs. However, they would demonstrate a tough resilience to both harsh conditions and severe casualties on active service. Cadorna came from an old Piedmontese military family. His father had commanded the army that entered Rome in 1870, sealing Italian unity. On the death of General Polio in 1914, Cadorna saw that the army was operationally unfit, and did much in the next few months to prepare it for war. From the outbreak of war he persisted with repeated head-on assaults, incurring enormous casualties. An austere and aloof man, ruthless to under-performing subordinates, he lacked the humanity that endears successful generals to their men.

The standard infantry weapon was the magazine-charged 6.5 mm bolt-action Mannlicher-Carcano rifle which dated back to 1891. It proved hard-wearing and its lighter caliber made it eminently suited to the mountainous regions where much of the fighting would occur. They were also equipped with Fiat-Revelli machine guns, which proved perfectly sound weapons – the problem was their scarcity. The Italians had a shortage of modern artillery. The most common field guns were the 75 mm Krupp or Deport models, with a number of 65 mm mountain guns which could be broken down to be transported by mules in rough country. But again there were simply too few of them, while heavy artillery was also in scarce supply. The Italians had none of the high-trajectory mortars that were so essential in mountain warfare. Throughout the years that followed, the Italians would be desperate for artillery support from their British and French allies.

The Italian Army deployed in the field in May 1915 thirty-six infantry divisions in fourteen corps, in contrast to the paltry six divisions of the British Expeditionary Force in 1914. And so the Italian entry into the war was a considerable blow to the Central Powers.

The Austro-Hungarian Army was already under relentless pressure in 1915. The addition of the Italians to its roster of enemies, which included the Russians and the Serbs, did not bode well. Yet in another sense the Italian timing was dreadful as it coincided with the advent of a massively increased level of support from Germany for the ailing Austria-Hungary on the Eastern Front. This would greatly ease the situation for the Austrians and allow them to reinforce the Italian Front in a manner which otherwise would have been impossible.

The Austrians had carved out extremely strong defensive works on the mountainous Trent and Alpine fronts, carefully using the terrain to their best advantage. Trenches, dugouts and gun pits were often blasted from the solid rock and covered by barbed wire. Given the precipitous nature of the ground, these positions would prove almost impregnable. Much work was also undertaken behind the lines to improve road and rail communications.

Overlooking and dominating the Isonzo sector were a series of mountains all heavily fortified: Monte Sabotino and Monte Podgora in an Austrian bridgehead to the west, and Monte Santo, Monte San Gabriele and Monte San Daniele to the east. Finally, as the Isonzo flowed down to the Adriatic, it passed the dominant Carso Plateau on its east bank, running parallel to the sea and rising up to 1,000 feet, with one of the key positions being Monte San Michele.

The defences on the Isonzo sector was not so well progressed, although the Austrian line was still intimidatingly strong, tucked onto the hills and ridges just behind the Isonzo River. In the Upper Isonzo the river ran through a deep gorge surrounded by the Bainsizza Plateau and Julian Alps. The Isonzo then ran through the Gorizia area, named after the town on its west bank.

The Austrian army was strong on tradition, many of its regiments claiming descent from those that had fought the Turks in the 17th century. With the steady expansion of the empire, however, it had been necessary to recruit increasingly from non-German elements. Problems of loyalty and language arose as German-speaking units became outnumbered by the other ethnic groups.

Shortly after the declaration of war, the Italians began their advance across the border, pushing forward to the Isonzo, while the Austrians fell back across the flood plain to the higher ground east of the river. At first the Italians made some useful gains, including the town of Caporetto in the north, and some progress in the Julian Alps east of the Isonzo, but ultimately their offensive ground to a halt.

Soldiers of both sides faced arduous conditions in the mountains. Cadorna planned a sustained offensive on the Isonzo and aggressive defence on the Trentino, whilst securing advantageous positions for his Alpini troops fighting in the high Carnic Alps.

The terrain would have tried the skills of the best mountain troops. Italy possessed such soldiers, recruited from its own alpine districts, but they were few in number, forming only two brigades equipped with their own mountain artillery. The majority of the army came from towns and farms, a quarter from the south and Sicily. The southerners had been subjects of the Kingdom of Italy for less than fifty years, had a low military reputation and looked to America rather than the cold and distant north as a point of emigration from their poor villages and overworked fields.

Initial results were gratifying and the Italians secured a number of positions inside Austrian territory on the Isonzo front, where the line stabilized, setting the scene for successive attritional battles.

The First Battle of the Isonzo followed shortly afterwards, with frontal attacks on the Austrian bridgehead opposite Gorizia and on the Carso Plateau. But these merely confirmed that any further advances would be extraordinarily difficult. Even where the Italians made small gains they were promptly hurled back by Austrian counterattacks.

The battle set a pattern for what would follow: the Italians used simplistic frontal tactics, relying on courage, élan and press of numbers to overwhelm the outnumbered Austrians, in which hope they were disappointed. Cadorna showed himself to be an utterly inflexible leader, supremely self-confident, apparently learning nothing from the rebuffs; indeed, he considered that failure originated in a lack of determination from his officers and men.

The thrust against Mount Mrzli began. Two days of bombardment were followed by an infantry attack. But a poor spring had yielded to a wet and squally summer. Torrential rain had turned the 40-degree hillsides into muddy pistes, exposed to Austrian fire. The mist that sometimes lay in the valley bottom afforded the only cover. Infantry on the higher slopes were unable to dig proper trenches in ground that was too muddy or too rocky. The attacks fizzled out.

On Mount Sleme a battalion of the Intra Brigade struggled up to the enemy wire, losing more than 300 men in the process. The commanding officer who had ordered the attack committed suicide.

The Italians were discovering that barbed wire was practically impossible to overcome. The Perugia Brigade tried to breach the wire on Podgora with gelignite tubes. Enemy fire was so intense that they could not get close to the wire. When the Italians attacked next day, regardless, the Austrians held their fire until the attackers were 30 paces away, while the artillery opened up against the reserves in the rear. No advance was possible.

The only sector where Italian operations avoided a fiasco was around the Carso, where the bombardment started against enemy lines near Sagrado. The Italian troops drove the Austrians back and got a foothold on Mount San Michele and Mount Sei Busi. An epic struggle for the westernmost heights of the Carso had begun.

Both sides knew the strategic importance of Mount San Michele. It formed an Austrian salient, protecting Gorizia and the Vipacco valley on one side and the Carso on the other. Without it, the Austrians’ defence on the lower Isonzo might unravel. The Italians advanced from their bridgehead at Sagrado towards the summit of San Michele, with a secondary thrust towards a rounded spur closer to the river, known as Hill 142. These blundering attacks pressed the Austrians harder than the Italians knew. Yet by the time extra forces arrived, the Austrian crisis was past.

On the southernmost sector, around Monfalcone, the Italian mood was gloomy. The first efforts to drive the Austrians off Mount Cosich and the neighbouring heights (Hills 85 and 121) failed badly. Even worse, the counterattacks created panic. The Italians were taking steady high losses from the machine guns across the valley.

In the Second Battle of the Isonzo, the story was essentially the same as the Italians charged forward time and time again – a story retold as tragedy. Although he had scraped together every possible gun from forts and naval sources, Cadorna still had nothing like enough guns or shells, or indeed gunners with the skills to accurately target Austrian strong points. The Second Battle was the first full-scale bloodbath on the front, costing 42,000 Italian casualties.

The Austrian positions were enormously strong, and both sides suffered terrible casualties. These were titanic battles: the Italians pitched 260 battalions against 129 Austrian, but despite this superiority the defenses proved too strong. Cadorna, never noted for his tolerance, had already sacked 27 generals and he removed many more in the months ahead.

One 32-year-old reservist rejoining the Bersaglieri in August 1915 was destined to make his mark on Italian history: Benito Mussolini, the editor of a socialist newspaper, was invalided out of the army following injuries sustained in a trench mortar accident, but not before he had been decorated for gallantry.

The Supreme Command took responsibility for coordinating the medium-caliber batteries and, instead of showering shells around the Austrian lines, the gunners concentrated on hitting the front line. This improved the results; the Austrians were stunned by the artillery fire, which continued into the afternoon. Yet the Italians still lacked detailed information about enemy positions, and did not realize that in many places the Austrians ducked into well-made underground shelters. The rear positions, on the other hand, were totally exposed, and the reserves took heavy casualties.

The main objective was Mount San Michele, at the northern tip of the Carso. The Italian infantry made good progress, quickly reaching the enemy lines on outlying summits and pressing upwards. The hilltop was stormed, but the triumphant Italians were hammered by accurate Austrian fire. The Austrians mustered forces for a counterattack. After an opening bombardment and two hours’ hand-to-hand fighting against a Bosnian regiment, the outnumbered Italians fell back to avoid being outflanked. They retook the hill twice, without being able to hold it.

The Italians made no more headway further north. Successive charges up Mount Sabotino and Podgora hill, around Gorizia, gained little ground against machine-gun enfilades. Marginal progress in the first days was wiped out by counterattacks. Repeated thrusts at Hill 383, above Plava, were repulsed.

For the soldiers, the Carso quickly became an evil force rather than an inert landscape: an enemy that probed their human frailty, flaying their senses. An Austrian officer remembered the vertical sun, ‘… baking the leaves on the trees to a dark crisp, until they crackle on the branch. It blanches the grass until it shatters at a touch, like the thinnest blown glass. In the glare, trees look black. Beyond, the sea steams, or gleams like steel. Rocks split. Sounds carry far louder and faster. It is as if the sun’s rays were multiplied by millions of mirrors, tormenting the soldiers’ eyes. There is no escaping the heat. Tongues swell, coated with thick saliva. Fingers swell and dangle clumsily from sticky hands. Eyes inflamed, skin like parchment. The blinding light beats everywhere, penetrating our eyelids. Our flasks are empty, sucked dry by early morning.’

On the upper Isonzo, the climate and conditions were atrocious in different ways that also added to the Italians’ difficulties. A junior officer called Virgilio Bonamore (3rd Company, 21st Battalion of Bersaglieri) kept a diary in the first months of the war. His company was stationed above Caporetto. He described nights at 2,000 metres, shivering uncontrollably on paths like goat-tracks where a wrong step meant certain death. On 29 July, he spent 24 hours in a trench between Mounts Krn and Mrzli, ‘ … squatting among our own and enemy corpses. The stench was unbearable and on top of that we had to withstand a furious enemy assault and we repelled it. Many of our men fell, hit in the head while they poked out of the trench to fire. The constant stream of bombs also caused some casualties. These are steel cylinders about 30 cm long that the Austrians throw at us with special equipment from up to 300 m away. Their effect is horrific. A poor Alpino lost his legs and had his stomach ripped out. In daytime you can see the bombs coming and dodge them but at night it’s serious stuff.’

During the third attack on the Isonzo front, the Italians were able to advance at Plava, near the Isonzo Canal and at Mount Saint Michele, in an attempt to outflank the Austrians defending Gorizia. In the end, however, the Austrians were able to hold their positions. Both sides suffered terrible casualties. The last days of the battle were extremely violent. Brigade diaries reported fears that some units might crack and desert en masse. The attacks on San Michele were weakening under the internal pressures of exhaustion and hopelessness. The Italians had sustained 67,000 losses along the front.

Cadorna was in no hurry to start a third offensive. Aware that his resources lagged behind the nation’s ambitions, he needed more heavy artillery and munitions if his breakthrough strategy was to succeed. He scraped together medium and heavy guns from far and near, including some naval batteries, and pushed the government to boost domestic production. The economy had to be put on a war footing. The government still regretted its dream of a short campaign and feared the public’s reaction when it awoke from the same dream.

The offensive started on a chilly autumn day. The bombardment was more intense than anything the Austrians had seen on this front. The Austrians, however, were more than ready. Very little was achieved on the northern Isonzo. The Italians had briefly recaptured the ‘Big Trench’ on Mrzli at the end of September, only to lose it to the usual ferocious counterattack. The Salerno Brigade took the Big Trench. The Italians made their first real grab for the elusive summit of Mrzli. They were driven back once, then twice. These failures were mitigated by advances elsewhere on the mountain, pushing the Austrians back towards the summit on either side of the Big Trench. But there was no breakthrough.

On the Carso, control of San Michele switched from one side to another amid savage fighting over three days. The Italians repeatedly overran the Austrian front line, but could not withstand the counterattack. Again and again, they charged at positions that turned out not to have been seriously damaged. Their assaults were stopped short by intact wire.

The Austrians had made good use of the quiet months since the Second Battle. By the time the Italians had taken the first line of enemy trenches, the enemy reserves had reached the second line, which was in better condition than the first line and well able to block any further advance while the Austrians prepared their counterattack.

The Siena Brigade’s task in the Third Battle was to take the Austrians’ long, well-fortified front line on Sei Busi. The trench was taken after three days of bloody assaults, with all three battalions engaged. The rejoicing was short-lived; that night, the Italians were driven back to their jump-off position. As usual, they had no time to prepare their defense. Soon afterwards the Siena Brigade was replaced with a regiment of Bersaglieri and the Sassari Brigade. Together, these fresh forces retook the trench, and kept it. Yet another massive effort had yielded a success which was scarcely visible on the map.

Bad weather lasted throughout the battle, intensifying at the end of October. By early November, the trenches were quagmires of filth, the roads almost impassable. The first snowfalls forced the fighting to stop.

During the Fourth Battle of the Isonzo the Italians were able to make small gains, capturing the hills overlooking Gorizia. On the other sectors of the front the Italians were not able to make any gains, despite brutal fighting and numerous casualties.

After a week’s pause, the Fourth Battle was launched with a short bombardment. The infantry did their best to charge up the open slopes of Mrzli, Podgora, Sabotino and San Michele, swept by machine-gun fire. The rain pelted down, the temperature sank, and then heavy snow fell.

Thanks to the wire and machine guns, Austrian units that had lost half their men held back Italian advances with three times their own strength. A bit of ground was taken here and there, after huge losses, but nothing decisive.

Amid the routine slaughter, 18 November marked a turning point: the Italians shelled Gorizia for three hours. This was the start of ‘total war’ on the Isonzo. Until now, both sides had mostly refrained from targeting civilians – though Austrian ships and planes had shelled several Adriatic cities in May 1915.

Why did Cadorna abandon the moral high ground now, when he knew that Gorizia could not be taken during this battle? His memoirs offer no clue. Perhaps he decided that civilized restraint had become a luxury, or the spectacle of the city’s near-normality so close to the front line harmed his own men’s morale. Whatever the reason, Cadorna privately admitted that Gorizia was more a political than a strategic objective, and the shelling brought no advantage to offset the propaganda loss.

The Supreme Command ordered a last offensive on Mount Mrzli and around Tolmein. Senior officers were unconvinced. Many of the men could no longer fit their boots onto their swollen feet, and frostbite was a danger. The mud, too, undermined morale: when their uniforms dried out, they were stiff as boards. Even so, the Italians pushed the Austrians back to within 20 metres of the summit. Taking advantage of a rising mist, the counter-attacking Austrians quickly drove the Italians back to the Big Trench.

Operations petered out in the first week of December, when heavy snowfalls obliterated trenches and wire. The Fourth Battle had added 49,000 Italian casualties to the 67,000 from the Third. Austrian losses were 42,000 and 25,000 respectively.

In their first four Isonzo attacks alone the Italians lost 161,000 men and the Austrians nearly 147,000 killed, wounded, captured and missing. More Italians were called from the reserve to the colors. As winter descended, the tempo of operations slowed, and cholera, supposedly contracted from the Austrians, spread through the Italian army.

The Italians were still short of artillery, especially the heavy guns needed to break up the Austrian defences. At an Allied summit conference at Chantilly it was agreed that Britain and France would provide additional guns and equipment to buttress the Italian war effort.

No reliable way had been found to breach barbed-wire entanglements. Heavy artillery could do it, but could rarely be spared for this task. Even when the gelignite tubes exploded (the fuses easily became damp and refused to ignite), the gaps were so narrow that they formed deadly bottlenecks when the Italians tried to crowd through – a gift to enemy machine gunners. Unless enough cylinders were used, the explosions failed to break the wire. Even then, the Austrians usually had time to patch over the gaps before dawn.

Even local successes had exposed crippling defects. When the Italians did manage to break into an enemy trench after heroic efforts, they seemed at a loss. Their resolve disintegrated at the first burst of gunfire, flurry of grenades, or bayonet charge. The Austrians found they could stampede the Italians back to their own lines quite easily. Cadorna was oblivious to such omens about training and morale.