The Trentino region was considered something of a backwater by most Italian soldiers in early 1916, especially when compared with the Izonso Front, which had witnessed the bulk of the fighting. All this changed with the approach of spring as Italian high command issued a flurry of orders, demanding trench lines be strengthened and reserve positions bolstered. Advanced positions that were untenable for defence were to be abandoned. Veterans might have scratched their heads at this, wondering what the fuss was about. Surely the Austro-Hungarians had a screw loose if they proposed an offensive across territory more often suited to herding mountain goats?
The answer came on May 14 when a fierce bombardment was unleashed on Italian positions. The following day, men who had believed they were on the war’s periphery were suddenly fighting for their lives, with hordes of pike-grey Austro-Hungarian infantry pressing forward as their artillery found other targets to pummel. While some raced ahead, others units were in for a shock as Italian resistance proved rugged, with many defending units fighting to the last bullet or the last man. And so began the one of the bloodiest campaigns ever fought in the Alps...
Since summer 1915, when Italy had dramatically entered the war on the Allied side, her armies had been nibbling away at Austro-Hungarian territory, particularly in the Isonzo region in the northeast. Although the cost had been high, the Italians stubbornly persisted in battering away at their enemy’s defences, firm in the belief that the edifice would eventually collapse. Victorious, Italy would claim the majority-Italian regions of Austro-Hungary in the north as her own and seek to claim much of the Adriatic region too. With the pressure mounting, Austro-Hungary was keen to pluck the Italian thorn from its side and concentrate on Russia, its main enemy. But how could this be achieved? The empire’s Supreme Commander, Conrad von Hotzendorf, believed he had found the solution by winter 1915.
Hotzendorf decided that Austro-Hungarian forces would launch a grand sweep through the mountainous Trentino region down into the Venetian Plain. Surprise and swift movement would be vital, along with superiority in numbers. Logistical difficulties would be immense but surmountable. Indeed, if events went according to plan, then fighting in the mountainous zone would only be a fraction of the overall campaign. The men would push through a frontage of around 50 miles (80km), stretching from the Adige valley to the Sette Comuni plateau, the main thrust punching through to the Val Sugnana and onto Thiene, Bassano and then Vicenza. Once in the lowlands, the Austro-Hungarian army would cut off the Italian army on the Isonzo Front from the rest of Italy. A defeat on this scale would shatter Italian morale and, with it, hopefully force the country’s surrender.
It was an audacious plan but one that would require Austro-Hungary to remove its best men and a great deal of materiel from the Galician Front in Poland. This was dangerous as Russia stood a good chance of inflicting major, possibly irreparable damage on Austro-Hungary’s position if she unleashed a well-directed offensive at the same time. But if German manpower was bought on board for the Trentino campaign, then Hotzendorf could leave a sizeable number of divisions in the East as a safeguard. Once Italy was knocked out, most Austro-Hungarian troops in the theatre could then rush east to combat Russia.
Hotzendorf sought aid from his German counterpart, Erich von Falkenhayn, requesting nine top-quality German divisions and accompanying artillery. But Falkenhayn thought Hotzendorf’s plan was overly confident; too much depended on events going smoothly, with little consideration for the usual mix-ups, breakdowns and misjudgements that occur during battle and across the supply chain. Falkenhayn also thought Hotzendorf’s proposed use of 18 Divisions was too few – 25 would be much better. Regardless of these personal misgivings, Falkenhayn’s hands were already tied as he was preparing for a massive offensive at Verdun, which would require every German soldier available in order to ‘bleed France white’ in a titanic battle of attrition.
Although disappointed with Falkenhayn’s opinion, Hotzendorf was not dejected enough to pack up his plans. Indeed, the negative response may have spurred him on; if Germany would not help, then Austro-Hungary would succeed alone and against the odds. Hotzendorf moved 13 divisions away from the Eastern Front and combined them with forces in the Trentino region to produce two armies: the 11th, under General Dankl, and the 3rd, under General Kövess von Köessháza. The armies were placed one in front of the other to act in tandem and create greater momentum when punching through the Italian lines. At the sharp end, 157,000 men had been gathered for the fight, with 1,977 guns in support. In total, 400,000 men, including vital supply and logistic units, would take part in Austro-Hungary’s offensive in some way or another. Of the artillery, 476 guns were of heavy calibre, including three 420mm monsters, some of the most powerful artillery pieces on the planet. In command at ground level was Archduke Eugen, with one of the corps placed in the hands of Archduke Karl Franz Josef, the future and last Emperor of Austro-Hungary.
Austro-Hungarian Command was quick to start planning, knowing the keys to success depended on solving the immense communications and logistics difficulties imposed by mountain warfare. It also appreciated that joint planning between commanders in the field was going to be difficult once the fighting started. Therefore, decision-making powers were devolved to corps level, with commanders told to use their best judgement as events unfolded. It was hoped the perceived lack of Italian morale and willingness to fight would make the job of attacking easier. If the Austro-Hungarians kept to their timetable, an acceptable level of communications could be re-established almost as soon as the final mountain barriers were passed. Another headache revolved around the question of food and water.
During the war, the Italians concluded a soldier needed around 3,900 calories per day to perform in combat conditions on the Alps’ middle ranges. For the Austro-Hungarians, trying to feed 157,000 men roughly 3,900 calories per day over this terrain was going to be immensely difficult and, in many places, simply impossible. Several major units were expected to rely on iron rations for days at a time once the offence started. In the event, this issue of supply proved critical as many officers were soon reporting fatigue among the men that was directly linked to the lack of calorific intake.
Many historians have presented the Italians not just surprised by the Trentino offensive but almost dumbfounded by its audacity and scale – a First World War example of ‘shock and awe’. However, the evidence shows otherwise; while not best prepared, the Italians certainly took measures to bolster their defences and were well aware that Austro-Hungary intended to make some kind of advance in the region. Their failures related to underestimating the scale of what was to come and some of the blame here rests with Italy’s supreme commander, Marshal Luigi Cadorna. He and other Italian strategists believed Austro-Hungary would not risk withdrawing her forces from the Russian Front. Thus he settled down planning yet another offensive on the Isonzo Front* and stressed to General Roberto Brusati, commander of 1st Army and in charge of the Trentino sector, that he should remain on the defensive. In addition, Cadorna sent some reinforcements, albeit small in number.
*There had been five there already.
For the Italians, it was most unfortunate that General Brusati liberally interpreted his orders. A ‘thrusting’ general, he liked to maintain an offensive stance and the front lines remained almost the sole centre of his attention. Advance posts continued to be pushed out as far as possible, while plans were still being made for small-scale actions to re-jig the line in Italy’s favour for attack. The second and third defence lines, the vital jump-back points to allow an army to bend in defence, were given less attention. According to Cadorna, the fourth and final line existed merely as a coloured marking on the maps.
Adding to the danger, Brusati placed too much of his artillery, supplies and munitions near the front. This was useful for an offensive, but played with fire when on the defensive. If the Austro-Hungarians punctured Italian frontlines then their precious artillery and support units could easily be compromised, while the destruction or capture of vital ammunition, rations and other supplies was highly likely. In addition, it would mean units falling back would be without the necessary artillery support, munitions and supplies that should have been on hand in the rear zones in case of emergency. Finally, the failure to strengthen the rear lines would make it much harder for Italian forces to stage counter attacks from secure strongpoints or jumping-off points.
By early spring 1916, intelligence unequivocally pointed to an offensive in the Trentino region by Austro-Hungary, although Cadorna still underestimated the scale. However, he was now concerned enough to visit the region and examine its state of defence. He was not best pleased by what he discovered. Cadorna moved his headquarters to the theatre in April and, while doing so, issued a raft of orders to strengthen the reserve lines and abandon advanced positions unfavourable for defence. Reinforcements were rushed up, including 67 additional battalions and 20 batteries, with the 9th and 10th Divisions placed directly behind 1st Army to act in a supporting role. Brusati was dismissed and General Guglielmo Pecori-Giraldi took his place.
Rather amazingly, it was hoped the Austro-Hungarian offensive would not upset Cadorna’s Isonzo plans and it is here that the Italian General deserves censure. Had he better understood the situation, Cadorna should have realised an offensive in a region like Trentino was going to be an all-or-nothing gambit; Hotzendorf's forces needed to be large enough to break through the mountain defences and move into striking distance of the alpine foothills.* If Cadorna had rushed more men to the defence lines, Austro-Hungary’s Trentino offensive may well have fizzled out far earlier than it did. In turn, this would have enabled the Italians to claim a morale-boosting victory. As it was, the Italians had only 118 battalions at the front, with 40 in reserve. They were supported by 623 guns, many of which many were antiquated as the Isonzo Front continued to take precedence in artillery. However, confidence among the troops was fairly good, despite the Italian infantryman’s miserable pay and almost complete lack of leave.
*In addition, Cadorna should have considered Hotzendorf's propensity for making all-out attacks, which had already delivered some decidedly mixed results on the Eastern Front.
Although fielding fewer men than they had hoped, the Austro-Hungarians were admirably prepared, with supply dumps bought forward and detailed plans for the initial phases of battle disseminated down the chain of command. In propaganda terms, the campaign was presented as a punishment expedition, strafexpedition, against Italy for breaking her alliance with the Central Powers and then joining the Entente to make her surprise attack in 1915. The prospect of food and loot once the Austro-Hungarians broke out of the mountain ranges was also alluded to and, such was the overall confidence, some of the officers had been supplied with tourist guides.*
*No doubt this was because they contained useful maps.
Austro-Hungarian high command knew from the bitter experience of fighting the Russians in the Carpathian ranges that it was vital to secure an army’s flanks in mountain warfare; it was no good taking vast chunks out of the centre only to face lethal harassing fire and counter attacks from surrounding heights and mountains. Therefore, areas to the left and right of the central advance would be assaulted first. Somewhat optimistically, Hotzendorf believed his campaign could start in April, which would give Austro-Hungary extra time to attack Italy and then return troops to the Eastern Front. But the weather remained so poor that the offensive was postponed for several weeks, providing the Italians vital time.
On 14 May, the Austro-Hungarians started a short and extremely sharp bombardment, with the battle for the flanks began starting the next day. In the northeast, an attempt to force the Val Sugana was unleashed, while a drive also started against the Italians between Val Lagarina and Val d’Astico. Here the men of Italy’s 37th Division were almost overwhelmed and forced to scrabble back to Col Santo (2,115m/6,930ft). With determination, the Italians held on until being forced back again on 18 May. German General von Cramon recorded the Austro-Hungarian opening moves as ‘magnificent’. Even the US Ambassador to Italy at this time, Thomas Nelson Page, had nothing but praise in his account of the action. He wrote: ‘The Austro-Hungarians knew every foot of ground: mountain and valley, and their attack was admirably planned and well carried out. Both artillery and infantry were skilfully handled.’ In the next breath he added: ‘The Italian advanced positions were swept away by the flood of shell poured out on them.’
But while the start had been spectacular, there were niggling points of worry for the Austro-Hungarians; the Italians may have been pushed hard but they were not cracking. Indeed, they were even putting up a spirited resistance in some sectors. Austro-Hungarian speed was being sapped as principal lines of resistance were formed at Coni Zugna and Passo di Duole. It was the scene of constant combat from 23 May to 28 May, the last day witnessing a whole Austro-Hungarian division thrown at a single defensive point that was initially held by a battalion from the Italian 62nd Infantry Division.
Looking at the scenery today, it seems incredible that such actions could have taken place in this location and on such a large scale. Woods intermingle with bare rock faces and scree, with much of the topography uninviting to all except the experienced hiker. Having to fight over this landscape pushed many men to the limits. The Italians quickly reinforced the beleaguered defenders with five other battalions. But despite inflicting heavy losses on the enemy, these additional men only managed to hold until 30 May. By now, ten officers and 148 men were dead, 28 officers and 583 men were wounded and 152 were listed as missing. It was impossible to hold on and so the Italians were forced to withdraw yet again. With covering protection from a force of Alpini,* the mauled units were able to pull back in fair order to set up new line of resistance at M. Cogolo-Novengo.
*Specialist troops for mountain warfare.
In the northeast, in the Val Sugana region, the Austro-Hungarian advance had started well, pushing aside Italian advance posts with ease. But the going quickly became tougher and, at some points, the Italians were even making audacious counter-attacks. For example, at Monte Collo (1,825m/5,985ft) the Ionio Brigade launched a localised assault, breifly putting their opponents on the back foot. Although pleased with the staunch defence their troops were making here, Italian high command made the sensible decision to have the line moved back to the torrent Maso, bringing a greater degree of uniformity to the front and easing the supply situation.
Meanwhile, the Austro-Hungarians resumed the offensive and between 25 May and 26 May fought and took possession of M. Civaron, but faltered in taking Monte Cima and Monte Ravetta. Away from these actions, fighting on the Folgaria plain started on the same day as the assaults on the flanks. Here the Austro-Hungarian corps under Archduke Karl advanced against the Monte Maronia-So d’ Aspio line and eventually drove the Italians back to tertiary positions on the Novegno group, south of Arsiero, which was almost the last alpine barrier before the foothills that led down into the Vicenza plain. With success tantalisingly close for the enemy, Italian High Command knew they had to hold firm here no matter the losses. They also needed to hold the centre ground as the main offensive had already begun.
Strike and counterstrike
The Austro-Hungarians were pushing across the Asiago plain. A massed bombardment started on 15 May, its intensity on a scale unprecedented for the Italian Front. Austro-Hungarian salvos pummelled the opposition, their blast effect made doubly deadly as the rocky ground flung up showers of lethal chips. The storm of steel lasted until 20 May when the main offensive was launched; the Italian Palermo and Ivrea Brigades found themselves in the thick of the action, holding on despite being outnumbered and outgunned. They were eventually dislodged and had to fall back to the next line of resistance. But the speed at which the Austro-Hungarians attacked, and their success at bringing up supporting artillery, compromised this position as well. The Italians soon found themselves retreating to the last marginal line of defence. Here too, they held on to the death, knowing full well that failure would result in the breakdown of Italy's defence.
On paper, the Austro-Hungarians now had every reason to celebrate. But their opponent's resolve remained unbroken and their was surprise at how adept the Italians had been in creating temporary stop-gaps and impromptu defence lines. Secondly, although significant ground had been gained in the centre and in the Archduke’s theatre, the Italian flanks had held up quite well. More frustratingly, the Austro-Hungarians found the Sette Communi plateau and upper portion of the Brenta valley to be a restricted place in which to manoeuvre or advance from. After the war, an Italian commentator neatly summed up the situation: ‘On this tableland of the Asiago… [Austro-Hungarian] battalions and artillery [were] all but smothered by their advance.’ But this assessment was written with the benefit of hindsight; at the time, Italy was thought to be in grave danger and reinforcements were desperately needed to prevent the enemy from gaining a second wind.
Fortunately for the Italians, General Cadorna had taken immediate efforts to get more men and materiel into place. Despite his deep and many flaws as a commander,* Cadorna was adept as a logistician. On 21 May, he issued an order announcing the creation of a new army, the 5th. Formed in the plains, it comprised five corps and a cavalry division, or about 400,000 men in total. For three whole days, northern Italy’s railway infrastructure was devoted to ensuring this force was put in position and it is a testament to thousands of unsung Italian railway workers that such a vast feat was accomplished in such a short period.
*He was known for unrelenting discipline, sacking many talented officers and condoning the over-use of capital punishment – several hundred soldiers were shot during Cadorna’s tenure. He was unimaginative on the offensive and frequently underestimated the enemy’s capabilities when defending. The nadir came during the Battle of Caporetto in late 1917, a near-disaster over which he presided.
Meanwhile, reinforcements closer to hand – 93 battalions and a smattering of artillery units – had already been rushed into the maelstrom. Knowing the Italians were sending in their reserves, and that time was running against them, the Austro-Hungarians redoubled their efforts. They attacked Monte Cimone, north of Arsiero, on 25 May and drove back two Alpini battalions, forcing the Italians into realigning their front. But ominously for the Austro-Hungarians, some of their units were siphoned off by high command for return to the Eastern Front as the threat of a Russian offensive was now considered imminent.
By 2 June, even though they remained on a defensive footing, the Italians felt the corner had been turned. Austro-Hungarian assaults started to lack the vigour of the earlier attacks. Indeed, Cadorna was now thinking about launching a counter offensive in the region. He would start by attacking the Austro-Hungarian flanks and then swinging his forces around the enemy, leaving them trapped in a pocket to be crushed. In the meantime, he continued to bolster the men’s morale. On 3 June he issued an order declaring: ‘Remember that here we defend the soil of our country and the honour of army. These positions are to be defended to death.’ On 4 June, the Italians received welcome news: the Russians had launched their long-awaited offensive and the following day marked the high tide of Austro-Hungary’s effort in the Trentino region. After this, men and materiel were sent to the East in a hurry. Indeed, an entire division left the offensive zone on June 5. The momentum was slipping away from Austro-Hungary and building on the Italian side.
Italy’s counter-offensive started on 14 June. Cadorna and his high command’s logistical skills were starting to pay dividends and the Italians now had a chance to punish the enemy. On 16 June, the main Italian attack began with four corps charging into the fray, pushing into the flanks as planned. Austro-Hungarian high command responded by ordering the suspension of any offensive operations in the region. But the Italians were soon driving the Austro-Hungarians back along all parts of the front. On 25 June, Austro-Hungarian high Command bit the bullet and ordered their units to retreat to a pre-prepared defence line that was ahead of the starting positions, although not by much. The Italians retook Asiago on the same day. What had once been a pretty Italian mountain community had been wrecked. War correspondent Julian Price was on hand to record the scene: ‘The spectacle was but a repetition of what I had seen on the Western Front; heaps of rubble and smouldering ruin on all sides.’
The Austro-Hungarian retreat was completed successfully, thwarting Cadorna’s hope of catching them in a pocket. The Italian general now had a choice to make: should he batter away at the Austro-Hungarian’s new defence line or return his attention to the Isonzo front? Both regions contained heavy defences but the Trentino would be a particularly difficult theatre in which to fight because of its topography. And if the Austro-Hungarians had proven one thing, then it was the logistical nightmare of fighting in the middle ranges. However, Cadorna still had momentum on his side, plus the opportunity to inflict further defeats on an enemy still reducing its numbers due to fighting on the Eastern Front. Italian troops were also on the offensive, with their morale growing with every metre gained. Cadorna chose to return Italy’s efforts back to the Isonzo Front. Italian offensive actions would continue in the Trentino region, but on a much smaller scale.
With the danger passing, the Italian public and politicians searched for a scapegoat for what was seen as a near disaster. They chose to vent their frustration on the government, which promptly collapsed. Premier Antonio Salandra was forced to resign and a new, national government came to power. In the long term, this was to prove beneficial for Italy’s war effort. What of the losses? Trentino had been bloodbath for both sides: the Italians suffered 15,000 killed, 76,000 wounded, 56,000 taken prisoner and 294 guns lost, although most had been put out of action as withdrawals took place. The Austro-Hungarians recorded 10,000 dead, 45,000 wounded and 26,000 taken prisoner, although many statisticians believe the true losses were larger. As Falkenhayn had predicted, the Austro-Hungarians bit off more than they could chew. With only 18 divisions fielded, it had been increasingly difficult to maintain the weight of their offensive.
Still, it had been a close-run thing and the last mountain barrier may well have fallen if fresh men had been on hand for a final push. But even then, Cadorna’s rapid organisation of the 5th Army meant the Austro-Hungarians would have faced a second gruelling battle, possibly being ground to a halt in the alpine foothills. Without doubt the final spanner in the works came from the Russian offensive that forced the withdrawal of urgently-needed men away from Trentino. To his credit, Hotzendorf at least recognised the campaign had failed and that his forces faced encirclement. His subsequent decision to withdraw to the best possible defence lines thwarted Cadorna’s ultimate goal of trapping and destroying the remaining Austro-Hungarians divisions. Yet, it was a bitter pill to swallow – the advance had gone not much further than its starting point.
Both sides learned much from going on the offensive, particularly when it came to logistics and the dangers of mounting a grand offensive in the middle ranges. Men fighting from rock face to rock face, up and down steep gradients and at high altitudes tire quickly. Without a constant flow of fresh forces to inject into the fight, maintaining momentum – absolutely vital in an offensive – was incredibly difficult, if not impossible. More dangerously, Italian High Command felt it was unnecessary to analyse and correct many of its initial defensive mistakes. While Brusati must take the blame for pushing his troops, supplies and guns close to the front, his attitude was not unusual and remained popular among Italy’s commanders well after the Trentino campaign. The notion of having strong defence lines on which to retire in case of danger was not one that found ready acceptance. This was to have dire consequences during the Battle of Caporetto, where Austro-Hungary – together with Germany this time – delivered a defeat almost simliar in scope to the one Hotzendorf had conceived back in the winter of 1915, with thousands of Italians killed and wounded, and hundreds of thousands taken prisoner. Fortunately for Italy and the Allies, this offensive was ultimately unsuccessful too.
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