<Ul> <Li> British Empire </Li> <Li> French Republic </Li> <Li> Russian Empire </Li> </Ul> <P> The war began with the Austrian attack invasion of Serbia on 28 July 1914, in response to the assassination of Archduke Franz Ferdinand . The Austrian Empire followed with an attack on the Serbian ally Montenegro on 8 August . On the Western Front, the two neutral States of Belgium and Luxembourg were immediately occupied by German troops as part of the German Schlieffen Plan . </P> <P> Of the two Low Countries involved in the war, Luxembourg chose to capitulate, and was viewed as a collaborationist state by the Entente powers: Luxembourg never became part of the Allies, and only narrowly avoided Belgium's efforts of annexation, at the conclusion of hostilities in 1919 . On 23 August Japan joined the Entente, which then counted seven members. . The entrance of the British Empire brought Nepal into the war . </P> <P> On 23 May 1915, Italy entered the war on the Entente side and declared war on Austria; previously, Italy had been a member of the Triple Alliance but had remained neutral since the beginning of the conflict . In 1916, Montenegro capitulated and left the Entente, and two nations joined, Portugal and Romania . </P>

Who was allied with germany during world war i