Caporetto

Strangely, the increasing toll taken on both sides meant that the decisive 12^th Battle of the Isonzo, better known as Caporetto, was completely different to the preceding eleven. The results of the artillery barrages of 10 and 11 had put the Italians across the Isonzo in the south, and on to the plains of Bainsizza and the Carso. But the efforts had exhausted the Italian armies, while the Austrian army under Borosevic was so weakened that he believed his only chance lay in a last desperate counter offensive.

Italians rounded up as prisoners
at Caporetto

In fact, Caporetto presaged the strategic change on the Western Front. In Isonzo 1-11 (as in every major Western Front action from Neuve Chapelle in March 1915 to Third Ypres)the pattern had been of Allied bombardment followed by the infantry throwing themselves against the well formed defences of the Central Powers. Ludendorff soon recognised the opportunity, provided by the collapse of the Russian front, to change the game. A combination of innovation in tactics and technology, linked with the weakness and exhaustion of the combatants made it possible. Much of the German army’s activity in the summer of 1917 was focused on the tactics – those of shock troops supported by rapid deployment of reserves; of gas attacks rather than prolonged opening bombardments. In summary, surprise rather than pulverisation. They were often known as ‘Hutier tactics’, after the General who first employed them in the capture of Riga in September 917, but he could not claim to have invented them.

Ludendorff, apparently the source of the ‘shackled to a corpse’ disparagement of Austria in 1915, was not keen to launch his new tactics in an Austrian cause, but on this occasion Hindenburg overruled him, and resolved to give German support to Austria’s hopes to knock Italy out of the war.

In October 1917 Italy was in a precarious state – economically, politically and militarily. Her population was worn down by the heavy losses – and hungry. In several cities there was unrest, particularly in Turin, the centre of armaments production. Sedition and propaganda caused a turmoil with riots in August 1917, superficially over bread shortages, but for much deeper reasons. Turin was declared a warzone under martial law, and many of the able bodied men were conscripted into battalions and sent, with no training, to the front near….... Caporetto.

The Italian government was struggling to retain its authority as a loose coalition. Its pacifist sections had been strengthened by a widely issued peace note from the Vatican in 1917 – much more influential in Italy than in other belligerent country. The Prime Minister Boselli was under attack from all sides, and would not survive the initial shock reactions to Caporetto.

The Italian army was exhausted and depleted. The Isonzo front was held mostly by Capello’s shattered 2^nd army, with d’Aosta’s 3^rd holding the southern section from the Carso to the sea (See Post 16/9/2017). Italian casualties from the 10^th Isonzo battle outnumbered the total for first nine, and losses in the 11^th were even worse than the 10^th. The situation was desperate, but Cadorna, the Commander-in-Chief, accommodate miles behind the front line, continued his merciless approach, which was to do little more than issue strident orders, blaming his officers and men for every failure. He was hated, and the men’s morale was at rock bottom.

German preparations, carried out with their customary efficiency and stealth, brought several Divisions trained in Hutier tactics and two Divisions of crack Alpine troops. More importantly they took over military command of operations. General Otto von Below was moved from the western Front to take control from the Austrian High Command (including the wretched von Hotzendorf). Below planned for surprise by selecting the upper Isonzo as his breakthrough point, rather than south of Tolmino nearer to the plains.

Italian intelligence was weak, and consequently their preparations were poor. Some rumours of German involvement reached Cadorna but he felt it more likely they would head for the Trentino region than the Isonzo. He kept most of his artillery in the south Isonzo front, leaving the upper reaches more vulnerable to attack.

The Caporetto Disaster. Everything between the Isonzo front in the East and the River Piave to
the West was conceded to the Austrians (with a little help form the Germans).
(Modified from Liddell Hart's 'History of the First World War) 

The onslaught began on 24^th October 1917. Below ordered initial infantry attacks along the whole 60 miles front, but he was concentrating on three sites between Tolmino and Saga in the mountains to make his breakthrough. The town of Caporetto was the middle of these, and it was the first to give way. Stunned and terrified by the speed of advance and the gas attacks, the Italians in Caporetto panicked, and either surrendered or fled in huge numbers. Within hours, thousands of Below’s men had poured through the widening gap and were surrounding defenders on the higher ground positions west of the river. Within two days the crucial Monte Maggiore defensive line had been passed, and Capello’s army was in full retreat on the plains to Udine, pursued by, among others, a certain Erwin Rommel.

On 28^th came the crisis that reverberated throughout the allied countries. Von Below had taken Udine and was heading across the plain to the River Tagliamento the next great natural barrier (see Map). Up to this point, the Duke d’Aosta’s 3^rd army had performed well, and held its positions on the plains east of Gorizia. But Below’s rapid progress towards the Tagliamento brought the risk of isolation beyond communication lines. An urgent retreat to the Tagliamento was begun, and on that day Gorizia, so hard won, was abandoned. Somehow, the nightmare retreat was managed. Buchan’s graphic account “For a moment it seemed that the Duke of Aosta would share the fate of Capello. A million of men were retreating along the western highways, encumbered with batteries and hospitals and transport, while by every choked route peasants and townsmen fled for refuge from the Austrian cavalry. Units lost discipline, orders miscarried, roads were blocked for hours, and all the while down from the north came the menace of Below, swooping southward to cut off all retreat. There had been nothing like it before in the campaign, not even in the Russian debacle of 1915, for then there had been great open spaces to move in.” The 3^rd army (most of it) just won the race to its river crossings. By 31^st October they had crossed to support the temporary line of the 2^nd army, strung out northwards on the right bank of the Tagliamento. D’Aosta’s rear-guard troops and masses of equipment were cut off and captured.

The first news of the Caporetto breakthrough had reached the Allies on 26^th October, and the British and French governments at once agreed to send five Divisions each to support the defence of Italy’s front. The British force would be led by Plumer, their best general, but it would take time to get there.

Cadorna realised that the Tagliamento line could not be held, and that a more extensive withdrawal would be necessary. The best defensive positions were to be found behind the River Adige, nearly one hundred miles back, but such a move would concede Venice and with it control of the north Adriatic Sea. Instead, the right bank of the River Piave, 30-50 miles back, was selected. Here the upper reaches were vulnerable, and it would be necessary to pull back the 4^th Army of de Robilant to the line of the river, so it would form a link between the remnants of the 2^nd army on its right, and the 1st army, currently facing the Austrians on the Asiago plateau, on its left (see Map, and post 3/11/2016).

Through early November the plan was executed with determination and skill. On 7^th November final positions on the Tagliamento were relinquished, and by 10^th a new line had been achieved. This retrenchment, allied to the actions of a new Government, led by Vittorio Orlando, restored some pride and a new sense of national unity. This was timely, as serious attempts were being made by the Austrians to break the new line. In this critical phase many gallant defensive actions were fought, upstream from the important town of Montello and the high ground of Monte Grappa between the Piave and Brenta rivers (see Map). De Robilant led his troops brilliantly, even though many of them were raw reserves or new recruits. Attempts further south by Borosevic to break through to Venice were repulsed.

Vittorio Orlando
The new PM helped turn around
Italy's prospects in late 1917.

Cadorna was finally sacked, being replaced by Diaz, and in early December a significant conference took place in Rapallo, northern Italy. The senior leaders there - Lloyd George and the new French and Italian Prime Ministers (Painlevé and Orlando) - took firm steps towards creation of the Allied Council at Versailles and a unified military command (Ferdinand Foch, who would be the first supreme commander, was also present).

In December, the British and French Divisions took their place alongside the Italian 4^th Army in the Montello sector. Von Below and his senior officers were recalled to the Western Front for planning purposes, and the immediate danger had passed.

So, from the disaster – desertion and humiliation – at Caporetto arose a new national unity in response, and a magnificent defence of the new line under its new Command. Italy’s losses were officially estimated at 800,000 ‘effectives’ (10,000 dead; 30,000 wounded; 265,00 prisoners; 350,000 missing and deserters, and 150,000 sick). She had all but collapsed, which might haver brought a premature overall defeat for the Allies. A close run thing.