Italy's involvement in World War I is often neglected with the Western and Eastern Fronts being the focal points of remembrance, but for the Italians, their involvement in WWI caused significant loss and human suffering. Italy joined the war in April 1915 and by the end of the war, it is estimated that 600,000 Italians were dead in combat and more than a million were wounded or crippled. The Italian government spent more on the war than it had in the previous 50 years. The war debt, food shortages, bad harvests and significant inflationary increases effectively bankrupted the country, with an estimated half a million civilians dying. In addition, the territorial gains were small in comparison to the monetary cost of the war - the debt contracted to pay for the war's expenses was finally paid back in the 1970s.
Leading up to WWI, Italy had formed an alliance with the Central Powers of the German Empire and the Empire of the Austria-Hungary in the Triple Alliance. Italy should have joined on the side of the Central Powers when war broke out in August 1914 but instead declared neutrality. The Italian government had become convinced that support of the Central Powers would not gain Italy the territories she wanted as they were Austrian possessions – Italy's old adversary. Instead, over the course of the months that followed, Italy's leaders considered how to gain the greatest benefit from participation in the war. In 1915, Italy signed the secret Treaty of London and came into the war on the side of the Triple Entente (Britain, France, Russia). By its terms, Italy would receive control over territory on its border with Austria-Hungary stretching from Trentino through the South Tyrol to Trieste as well as other areas. The Triple Entente countries saw a way of weakening the Central Powers by opening up a new front and thus splitting them still further with a Western, Eastern and now Southern Front. The success of this depended on Italy making military progress into Austro-Hungary in the south, but this did not transpire.
Italy had only become a unified nation in 1859, and so, like Russia, was not yet a fully industrialized power and was still largely an agricultural country, with a weak economy. It lacked both the large military and industrial base of her enemies and was certainly not prepared for large-scale warfare. The new front was along Italy's northern border which was 400 miles long, mostly in the mountainous Italian Alps and along the Isonzo river. Despite being numerically superior, the Italian army were poorly equipped, lacked strategic leadership and were unable to move equipment and supply lines quickly. In addition to which, the Austrians owned the higher ground and so consequently, after several quick Italian successes on the Isonzo front, combat settled into stalemate. As in the Western Front, it became trench warfare with the Italian army repeatedly attacking Austria, making little or no progress and suffering heavy losses. However, unlike the Western Front, the main difference was the fact that the trenches had to be dug in the Alpine rocks and glaciers instead of in the mud and often up to 3,000 m of altitude.
Between 1915 and 1917, Italian troops only advanced 10 miles inside Austrian territory, having launched eleven offences in Isonzo with heavy losses on both sides. The frequency of offensives for which the Italian soldiers partook, one every three months, was higher than demanded by the armies on the Western Front and had a significant effect on morale. During this stalement, in 1916 the Austro-Hungarian army counter-attacked in the Battle of Asiago in Trentino, which also failed. In late October 1917, Germany intervened to help Austro-Hungary, by moving seven divisions from the Eastern Front when Russia withdrew from the war. This resulted in a victory over the Italians in the Battle of Caporetto (otherwise known as the Twelfth Battle of the Isonzo). When the battle had run its course, 11,000 Italians were dead, more than a quarter-million had been taken prisoner and Italy had retreated well behind their original lines. Caporetto was an unmitigated disaster and the whole Italian front along the Isonzo disintegrated, sparking a crisis in Italy. With the Central Powers now threatening Italy's territory, the Government changed tactics and implemented more defensive military strategies, replaced the Chief-of-Staff, improved soldier morale and Allied troops arrived (mainly British and French) to reinforce the front.
In the spring of 1918, Germany pulled out its troops for use in its upcoming Spring Offensive on the Western Front and due to increased civil unrest in Austro-Hungary, the Italian and Allied troops attacked on 24th October 1918. The Austro-Hungarian army finally broke, and the Allies drove deep into Austria, becoming the first troops to cross the pre-war boundaries. Once the line was broken, the advance was so fast that the Allied supply lines took two days to reach the troops at the front pushing into enemy territory. Austria asked for an armistice which was signed on 4th November 1918, a week before the general armistice. It is an often over-looked part of WWI history that the British fought alongside the Italians but in the mountains around Asiago in northern Italy, there are 712 British soldiers who now lie in cemetries.
After the war ended, at the Paris Peace Conference that led to the Versailles Treaty, the Italian government struggled against the other Allied leaders, the Big Three (Britain, France and the US), to gain all that they believed had been promised to them. Although Italy did receive control of most of the European requests, they failed to gain their colonial ambitions and felt they did not get what they had been promised. This engendered resentment towards the Allied countries, especially as Italians felt they had paid a high price, in terms of men and money, fighting for the Allies. These resentments helped drive the success of Benito Mussolini and his fascist movement - four years after the war, Mussolini and his blackshirts gained power.