When World War I started in 1914, Italy was in a defensive alliance with the Central Powers - Germany and Austria. However they decided to remain neutral in this war for a good reason: they had no territorial claims against the Entente Powers - France, Britain and Russia. Furthermore, there were still substantial Italian populations in the Northeastern part of the peninsula and in Istria and Dalmatia who were under Austrian sovereignty. This led Italy to join the Entente and declare war on Austria in 1915.
Being on the winning side allowed Italy to annex new territories under the auspices of the Paris Conference, namely Trentino-Alto Adige, the Julian March, Istria and the city of Zara (now Zadar, Croatia) on the Dalmatian coast. While substantial, these gains were less than they had hoped for and would create a nationalistic resentment that ultimately led to an alliance with Germany in 1939.
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Italy's WW1 Territorial Gains
