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Which side did Italy fight on during World War I?
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During World War I, Italy fought on the side of the Allied powers, which included France, Britain, and Russia.12
Although Italy was originally part of the Triple Alliance with Germany and Austria-Hungary, it remained neutral when the war began in 1914. In April 1915, Italy signed the secret Treaty of London, in which the Allies promised significant territorial gains—including Trentino, Trieste, and parts of Dalmatia—in exchange for Italy joining the conflict.3412
Italy officially declared war on Austria-Hungary on May 23, 1915, and later declared war on Germany in August 1916.42