The Treaty Of Vienna Made It Possible
Both sides signed the Treaty of Vienna in 1866, and for the next few years, they lived in relative peace. During the commencement of hostilities in July 1914, they had even been allies. Old conflicts between the two began to resurface as the complex battle extended across the region.
Following the London Treaty
By signing the Treaty of London in 1915, Italy broke loose from the Triple Alliance it had created with Germany and Austro-Hungary. This meant that the two entities on opposite sides of the Stelvio Pass were at odds. In the conflict, Mount Scorluzzo, which separated them, had a number of benefits.