Treaty of London ( 1915 ) London Pact ( ) , or more correctly , the Treaty of London , 1915 , was a secret pact between the Triple Entente and Italy , signed in London on 26 April 1915 by the United Kingdom , France , Russia , and the Kingdom of Italy . Its intent was to gain the alliance of Italy against its former allies , including Germany . According to the pact , Italy was to leave the Triple Alliance and join Triple Entente , as already stated in a secret agreement signed in London , on 4 – 5 September 1914 . 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 " . Paris Peace Conference . After the war , Italy would only negotiate with Serbia and Montenegro . The Italian delegation staged a walk - out for a number of months when faced with the denial of their territorial demands . The pact was nullified by the Treaty of Versailles . Before 1918 , the contents of the Pact of London had been published to the world by the Bolshevik Russian State . The Fourteen Points , as proposed by U . S . President Woodrow Wilson , contained a number of clauses that argued for ethnic or national self - determination and against respecting the provisions of the Treaty of London : In Wilson ' s view , the Pact of London had been arrived by secret contract , hence was not valid . Overall Wilson sought to achieve borders being determined by the populations present in the area rather than by outside parties ; the pact of London adjudicated to Italy areas that did not have a majority - Italian population . Wilson believed that Slavic claims to some of the disputed regions were more sound than those of Italy . Italy ultimately was denied other gains promised in the Treaty : a share of German colonies and control of Albania . They tried to establish a physical claim in Anatolia ( Turkey ) , but were quickly forced to evacuate . The partition of the Tyrol on the water divide line was confirmed by the Treaty of St . Germain . Repercussions of the disavowal of the Treaty . Some of Italy ' s demands for territory , as proposed in the Treaty , were both excessive and unworkable . The British and French leaders believed that the effective Italian contribution to the outcome of the war was limited , and they easily broke with the promises in the treaty once these became public and caused outrage . The irredentist nationalist element of Italy considered this an inexcusable betrayal by these two European allies . The colonial gains by England and France from the war further angered the Italians , who felt excluded . The breakdown of the London Pact helped give rise to a belief in a so - called " mutilated victory " within Italy , which played a role in determining Italian inter - war imperialism . In 1920 Italian nationalists created the Free State of Fiume , although it had not been assigned to Italy in the Treaty of London . This underscored the unstable results of the Treaty of Versailles relative to Italian claims . References . politics