On the morning of 15 May 1916 the Austro-Hungarian guns on the Trentino front opened fire on the Italian lines. It was the start of an offensive meant to break out of the Alps onto the Venetian plain and cut off the Italian armies fighting on the Isonzo. Italians remember it as the Strafexpedition, the punitive expedition. The attack overran mountain positions and much of the Asiago plateau before it lost its momentum, and it helped bring down the Italian government.
A blow from the mountains
Italy had entered the war against Austria-Hungary in May 1915, and its commander, General Luigi Cadorna, put his main effort into a series of offensives on the Isonzo River in the east. The Trentino, a wedge of Austrian territory pointing south into Italy, stood behind the left flank of those armies. The Austro-Hungarian chief of staff, Franz Conrad von Hötzendorf, planned to strike from there. According to Tiziano Bertè, a historian working with the war museum at Rovereto, the aim was to break the Italian line, come down onto the plain and cut the communications of the Isonzo front, trapping the Italian armies there. Bertè says Conrad asked the German chief of staff, Erich von Falkenhayn, for reinforcements in December 1915, but Germany was preparing for Verdun and gave none.1
The name Strafexpedition was not the official one. The Friuli Venezia Giulia regional tourist board describes the offensive as a punitive expedition against the Italian traitors, meaning Italy's desertion of its prewar alliance with Austria and Germany. Bertè says the name came from an Austrian deserter at Lavarone who told his interrogators he had heard officers talk of a punitive expedition; the Austrians themselves called it the spring offensive of 1916.2
The offensive of 15 May
The artillery opened fire on the morning of 15 May. Britannica writes that the offensive took the Italians by surprise, and the regional tourist board says Cadorna was caught off guard because he was convinced the Austrians would stay on the defensive. Within days the attackers took Col Santo on the Pasubio massif and other heights and pushed the Italians back toward Arsiero and onto the Asiago plateau. Bertè notes that the plan was widened to include the Valsugana, which spread the attack more thinly and made it easier to stop.3
Prisoners were taken in large numbers. Among them were Cesare Battisti and Fabio Filzi, Italian nationalists from the Trentino who had been Austrian subjects; the regional tourist board records that they were identified, tried for high treason and hanged at Trento. Bertè adds the young officer Damiano Chiesa from Rovereto, captured in the first days and shot at Trento on 19 May.4
Why the attack stalled
The danger of a breakthrough into the plain was averted. Bertè explains that once the Austrians had broken the first line, they could not bring their heavy guns forward fast enough, and the Italians had time to rebuild their defense. Cadorna brought troops over from the Isonzo and formed a new Fifth Army between Vicenza and Cittadella. Italy also asked Russia for help. Britannica says the Italians appealed for an attack that would draw Austrian reserves away, and that General Aleksei Brusilov brought his offensive forward to 4 June in response. By the end of May the Austrian push was losing strength, and only around Asiago did the attacks go on into June.5 › Brusilov Offensive, 1916
Bertè gives Italian losses in the offensive, killed, wounded, missing and captured, as almost 70,000, and Austrian losses as less than half that. The Italian counteroffensive that began in June won back only about a third of the ground lost north and southwest of Asiago, according to Britannica.6
Consequences
In Rome the crisis brought down the government of Antonio Salandra; Britannica says he was forced to resign in 1916 because of Italy's growing military difficulties. On the front, the line in the mountains froze again into trench warfare. In August Cadorna returned to the Isonzo and in the Sixth Battle took Gorizia, Italy's first real victory of the war. The great Italian defeat on the Isonzo came a year later, and is told on our page for 24 October; the wider war is in the greatest battles of World War I.7
Also on this day
- 1943: Operation Schwarz. German and Italian forces launched a joint offensive to trap and destroy the main Yugoslav Partisan army by the Sutjeska river in Bosnia.
