Sixth Battle of the Isonzo


The Sixth Battle of the Isonzo also known as the Battle of Gorizia was the most successful Italian offensive along the Soča River during World War I.

Background

had reduced the Austro-Hungarian forces along the Soča front to reinforce his Trentino Offensive and also to assist with the defense of the Russian Brusilov Offensive then taking place on the eastern front. Italian Chief-of-Staff Luigi Cadorna turned his attention to the Isonzo front and particularly, the city of Gorizia. They planned a heavy bombardment in a very restricted zone between Monte Calvario and Monte San Michele – two heights overlooking the city. The bombardment would be followed by ground action to obtain control of the left bank of the Isonzo. Moreover, this battle would start with an advantage because the Italians had already succeeded in advancing towards the top of Monte Sabotino another height above Gorizia and Italian sappers had built several tunnels behind the emplacements of the Austro-Hungarian troops there.
Cardona also made good use of railroads to quickly shift troops from Trentino back to the Isonzo line for this offensive against the weakened Austro-Hungarian defenses.

Battle

On 6 August the offensive was launched against Gorizia. The offensive was concentrated in two zones: the hilly area west of the Soča river near Gorizia and the westernmost edge of the Karst Plateau near Doberdò del Lago. In the Battle of Doberdò, the Italians, after bloody hand-to-hand combat, managed to conquer the main transport road leading from the coast town of Duino to Gorizia, thus securing their advance to Gorizia from the south. The Austro-Hungarian forces had to retreat on the line east of Gorizia, leaving the heavily damaged town to the Italians.
The bombardment at Gorizia was extremely heavy and effective. Borojevic asked for reinforcements but was denied. In the afternoon Cadorna ordered the 45th division to attack Monte Sabotino. In under one hour, supported by heavy artillery, the Italian infantry reached the peak.
Simultaneously the attack on Monte San Michele also commenced. The Italian Infantry succeeded quickly to reach the summit while the Austro-Hungarian soldiers retreated waiting for a later counterattack. In the absence of reserve forces, that counter failed.
With the conquest of Monte Sabotino and Monte San Michele, the previously strong Austro-Hungarian defensive line around Gorizia rapidly disintegrated. Then Monte Calvario fell during that night. On the right bank of the Isonzo there was only one regiment who then withdrew to the east on August 8. The first platoons of the Pavia Brigade began to enter the city. Gorizia fell to Cadorna and a bridgehead was finally established across the Soča River. The Austro-Hungarians shifted troops to the Gorizia sector to prevent a breakthrough.
Borojevic, had already ordered his men to retreat further to the east, into a valley called The Vallone. Thus strategic positions on the western Carso such as Monte Sei Busi, the zone around Doberdò del Lago and Monte Cosich to the north of Monfalcone were thus abandoned.
However, the Austro-Hungarian defenses in the north and east of Gorizia still included an uninterrupted series of heights – including ridges from Monte Santo, Monte San Gabriele, Monte San Daniele. These heights and Quota 383 lent themselves to place the Austro - Hungarian artillery and provide excellent observatories after the fall of Gorizia. These heights had been prepared for defense purposes and made it possible to block any passage towards by the Italian troops to Vienna and Trieste.
The new Austrian front line now passed to Nad Logem, Quota 187, Opacchiasella, Nova Vas and Quota 208 north and south, Quota 144 and Quota 77 and the Austro-Hungarian troops engaged the Italians in a series of heavy, defensive firefights.
Content with having established the bridgehead, capturing Gorizia and the western Karst, and having suffered heavy losses, Cadorna ended the offensive on 17 August.
The attack on Gorizia was the most successful Italian offensive along the Isonzo lines and greatly boosted Italian morale - especially since Gorizia had been promoted as a desirable objective, unattainable in earlier battles. In the wake of the battle Italy finally declared war against Germany, on 28 August.