Treaty of London (1915)

London Pact (Italian: Patto di Londra), or more correctly, the Treaty of London, 1915, was a secret pact between the Triple Entente and the Kingdom of Italy. The treaty was signed in London on 26 April 1915 by the United Kingdom of Great Britain and Ireland, the French Third Republic, the Russian Empire, and the Kingdom of Italy. Its intent was to gain the alliance of Italy against its former allies, including German empire and Austro-Hungary.

According to the pact, Italy was to leave the Triple Alliance and join Triple Entente; Italy was to declare war against Germany and Austria-Hungary within a month (this happened against Austria-Hungary within a month, but not until 1916 against Germany). Assuming victory against Germany and its allies, the Triple Entente promised Italy the following territorial gains (see Italia irredenta) at the end of the war:

The Kingdom of Serbia, which was not present nor a signatory, was assigned:

The Kingdom of Montenegro, which was not present nor a signatory, was assigned:

Also, but less precisely, Serbia was assigned:

Italy insisted, and the Allies agreed, that the question of the Adriatic coast between Zara and Istria should be settled after the war. Italy also insisted that Serbia should not be informed about the agreements. However, the Allies overruled this by sending an official note to Serbia on 4 August 1915, confirming the post-war territorial claims of Serbia and Montenegro.

The pact was to be kept secret, but after the October Revolution in Russia, it was published in November 1917 by the Russian journal Izvestia.

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