End of the Eleventh Battle of the Isonzo

On 12 September 1917 the Italians stormed Monte San Gabriele in full strength for the last time. For three weeks this mountain above Gorizia had been the scene of the bloodiest part of the Eleventh Battle of the Isonzo. After many hours of fighting around the summit, the attack collapsed. The next day there was one more attempt, and then the bombardment began to slacken. The greatest offensive of the Italian army in this war had come to an end. That same day the Austro-Hungarian command of the South-Western Front received orders to prepare an offensive that it was to carry out together with the Germans.

The last fighting for San Gabriele

Italy was beginning to feel the effects of exhaustion. On 1 September the Italian Supreme Command postponed the previously announced great attack on the hills around Gorizia to the end of September, because stocks of ammunition for medium and heavy guns had come close to the fixed minimum below which they could not be used. The commander of the Second Army, General Luigi Capello, believed, however, that San Gabriele had to be taken at once and went on throwing his divisions against it. The Austrians too were at the end of their strength. On 5 September General Svetozar Boroević reported that despite enormous sacrifices the mountain might perhaps not be held. The two worn-out divisions defending San Gabriele, the 57th Infantry Division and the 106th Landsturm Division, which now numbered little more than a thousand rifles, were withdrawn to the rear. The situation was improved by the arrival of the Upper Austrian 14th Infantry Regiment and the Hungarian 20th Honvéd Infantry Division.

The 14th Regiment was to clear the summit, but Boroević ordered it to wait until the artillery was ready for coordinated fire. The commanders on the spot could not bear the tension and on the evening of 10 September sent the regiment into the attack before the preparations were complete. The companies, climbing the slopes in the dark under fire, did not reach their starting positions in time. The group that was to take Hill 552 postponed its attack to the following night. The second took the trenches on Hill 448 but had to give them up. Before dawn on 12 September the Upper Austrians made a surprise attack on Hill 552, took it and, according to the Austrian official history, captured 600 prisoners and 12 machine guns. They struck just as the Italian Foggia and Girgenti brigades, reinforced by Alpini units, were preparing to assault after three days of “siege by fire”, in which Capello’s batteries had fired about 45,000 shells at the mountain. For many hours on 12 September both artilleries pounded the masses of fighting men, and the heaviest clashes were fought for the summit itself. The Italians gained nothing. The heir to the traditions of the 14th Regiment in the Austrian army celebrates 12 September as its regimental day.

On the Bainsizza plateau local fighting continued through September. The Italians attacked to improve their line, and on 29 September the Sassari Brigade took the Gomila hill south-east of Madoni. It proved to be the easternmost point the Italians reached before the autumn retreat.

The balance

Both sides claimed victory. The Italians pointed to the largest territorial gain of all the battles on the Isonzo: on the Bainsizza plateau they had advanced about 10 kilometres. The Austrian official history recalled, however, that after thirty months and eleven battles the furthest advance of the Italian front, measured from Sagrado to Kostanjevica, amounted to 12 kilometres, a third of the way to Trieste. In June 1915 the Italians had begun the war on the Isonzo with 18 divisions and 750 guns; in August 1917 they threw 51 divisions and about 5,200 guns and trench mortars into the attack. Austria-Hungary had fielded eight divisions with 354 guns in 1915, and now 24 divisions with 1,880 guns and 300 mortars. In Italy great promises were followed by disappointment.

For the Austrians, however, it was a Pyrrhic victory. According to their official history, about 38 per cent of the Austro-Hungarian guns on the Isonzo were worn out and unfit for use, and replacements were lacking, because almost the only men returning to the ranks were recovered wounded. The Austrians were convinced that they would not survive another such battle and that the only way out was a pre-emptive strike.

The road to a joint offensive

The Austrians had been pressing for it since the end of August. On 29 August the head of the operations department of the Austro-Hungarian High Command, Major General Alfred von Waldstätten, came to German headquarters at Kreuznach. General Erich Ludendorff preferred to complete the conquest of Moldavia and did not want to weaken the front in Flanders, but Field Marshal Paul von Hindenburg agreed to send to the Isonzo a Bavarian specialist in mountain warfare, Lieutenant General Konrad Krafft von Dellmensingen. On 5 September Emperor Charles I, who had earlier wanted to fight the Italians with his own troops alone, agreed to the participation of German divisions. On 8 September Krafft reported at Kreuznach that an offensive from Tolmin lay “at the limit of the possible”, but he recommended it. Hindenburg agreed, and Waldstätten sent to Austrian headquarters at Baden the code agreed by telegram: “Waffentreue gesichert!” (“Loyalty in arms assured!”).

On 10 September the two headquarters agreed the details, and on 12 September the command of the South-Western Front received its orders. The attack was to be made by the new German Fourteenth Army of General of Infantry Otto von Below, with Krafft as chief of staff, six German divisions, including the Alpine Corps, and three Austro-Hungarian ones. The offensive was to begin between 10 and 20 October and push the Italians back beyond the border of Austria-Hungary and, if it succeeded, beyond the Tagliamento river. Six weeks after the end of the Eleventh Battle of the Isonzo, the attack from Tolmin led to the Italian defeat at Caporetto.