The Austrian Littoral was a crown land (Kronland) of the Austrian Empire, established in 1849. It consisted of three regions: the Margraviate of Istria in the south, Gorizia and Gradisca in the north, and the Imperial Free City of Trieste in the middle. The region has been contested frequently, with parts of it controlled at various times by the Republic of Venice, Austria-Hungary, Italy, and Yugoslavia among others.

The Treaty of London or the Pact of London was a secret agreement concluded on 26 April 1915 by the United Kingdom, France, and Russia on the one part, and Italy on the other, in order to entice the latter to enter World War I on the side of the Triple Entente. The agreement involved promises of Italian territorial expansion against Austria-Hungary, the Ottoman Empire and in Africa where it was promised enlargement of its colonies. The Entente countries hoped to force the Central Powers – particularly Germany and Austria-Hungary – to divert some of their forces away from existing battlefields. The Entente also hoped that Romania and Bulgaria would be encouraged to join them after Italy did the same.