Erik Sass is covering the events of the war exactly 100 years after they happened. This is the 235th installment in the series.
May 15, 1916: Austrians Launch “Punishment Expedition” Against Italy
Ever since Italy’s “treacherous” declaration of war against Austria-Hungary in May 1915, Austro-Hungarian chief of the general staff Conrad von Hötzendorf had burned with desire for revenge against the wayward member of the Triple Alliance – an ambition shared to varying degrees by Emperor Franz Josef and other members of the empire’s conservative aristocratic elite.
However Conrad’s hopes for vengeance had to be put on the back burner for the better part of a year due to far more pressing issues: in 1915 Austria-Hungary’s powerful ally Germany gave top priority to their joint spring offensive against Russia, followed in the fall by the joint campaign to crush Serbia, opening a line of communication with the embattled Ottoman Empire via Bulgaria. Meanwhile Habsburg forces, well entrenched but outnumbered, were forced to maintain a defensive posture on the Italian front in the face of repeated offensives along the Isonzo River, including the First, Second, Third, Fourth, and Fifth Battles of the Isonzo.
The situation looked considerably more favorable by the spring of 1916, as the Central Powers completed the conquest of Serbia and the defeat of Russia’s offensive at Lake Naroch in March 1916 convinced Conrad – like his German counterparts – that Russia’s offensive capability was largely exhausted (this proved badly mistaken).
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Perhaps most importantly, Conrad was angered by the German offensive at Verdun, launched by German chief of the general staff Erich von Falkenhayn amid complete secrecy, leaving Germany’s main ally in the dark about his plans. Conrad had originally hoped to have German support for his planned “Strafexpedition” or “Punishment Expedition” against Italy, but Falkhenhayn refused, and Conrad – furious at Falkenhayn’s failure to consult him about Verdun – decided to go ahead with an attack using only Habsburg troops.
The “Trentino Offensive,” also called the “Battle of Asiago” and “The Battle of the Plateaux” because of the battlefield’s geography, enjoyed unusual success in its opening days thanks to the element of surprise, as it fell on a previously quiet sector, and Conrad’s own thorough planning (a talent mostly overshadowed by Conrad’s German colleagues, who dominated in other theatres). However it fell far short of Conrad’s goal of a breakthrough from the central Alps down into the plains of northern Italy, cutting off the main body of the Italian armies further east.
To carry out the offensive Conrad assembled a very large force of 18 divisions, many of them drawn from the Eastern Front and Serbia, to buttress the Austro-Hungarian Third and Eleventh Armies recently redeployed from the Balkans, now stretched across the mountain ridges and foothills of the central Italian front; this gave the Habsburgs a local manpower advantage of four-to-one in infantry. Conrad also scraped together 2,000 artillery pieces to blast through the Italian lines, compared to just 850 on the Italian side.
On May 15, 1916, the two Habsburg armies unleashed a furious artillery bombardment that set fire to pine forests and meadows across the Trentino, then advanced against the outnumbered Italian First Army along a 40-mile front southeast of Trent itself. The first three days saw substantial progress by the standards of the First World: from May 16-18, the Austrians captured Italian trenches at Soglio d’Aspio (below) and took possession of the key mountain peaks of Zugna Torta, Monte Maggio, and Cimi di Campulozzo.
By May 19, however, the initial Austrian offensive was grinding to a halt, giving the overtaxed Italians an important respite that allowed them to build and strengthen new defenses. Meanwhile Italian chief of the general staff Luigi Cadorna frantically called up more reserves and formed the new Fifth Army near Vicenza beginning May 21; in the weeks to come the new army would help to stem the Austrian tide.
In the short term the Italian First Army faced renewed Austrian attacks by itself, and on May 21 the Austrian Third Army advanced again, capturing Monte Cost’alta and the Armenterra Ridge. The on May 23 the Italians fell back between Astico and Brenta, followed by Monte Cimone and Bettale on May 25. On May 26 the Austrian Third Army captured Mount Kempel and the Habsburgs shifted their main attack to the Asiago Plateau, which was abandoned by the Italians on by May 29; the Austrians occupied Asiago itself on May 31 (the town was largely destroyed during the war, below).
This proved to be the end of the Habsburg Strafexpedition. After attacking along a front from Posina to Astico on June 1-2, the Austrians were defeated at Civo on June 4, followed by two more defeats south and west of Asiago on June 7. At this point external events intervened, with the opening of the Russian Brusilov Offensive on the Eastern Front, forcing Conrad to withdraw two divisions from the Italian Front and end the offensive. The price of punishing Italy in the Trentino Offensive from May 15-June 4 numbered 100,000 Habsburg casualties, including 15,000 dead, while Italy sustained 140,000 casualties, including 12,000 dead.
Both sides now settled into another period of stasis, but even these were destructive in the First World War, requiring constant streams of supplies and fresh troops to the front – a remarkable feat considering the primitive, precipitous Alpine roads. Julius Price, a British war correspondent and artist, described the epic efforts required to supply Italian armies in the foothills of the Alps:
… one passed what was practically an endless convoy of munition trains, motor-lorries, picturesque carts from every corner apparently of the peninsula, and long strings of pack horses and mules. In and out of this imposing column and up the steepest parts of the road dispatch riders on motor bicycles dashed along with reckless speed and marvellous dexterity.
On a similar note Will Irwin, an American correspondent, recalled the engineering efforts and sheer brute force employed on the Italian side:
At one point a gang of soldier labourers dug a new road with pick and crowbar and blasting powder. At another a gang cleared… the way through an old road that had been smothered in an avalanche. Once… I saw along a white mountain-side a long string of men… When I put the glasses on them, I found that they were dragging a gun, mounted on sledges. Up they went, making almost imperceptible progress, across a slope on which a man could scarcely stand without the help of steps. Everywhere were trains of mules packed with explosives, with shells, with food, with clothing… lurching along the edges of the precipices.