<P> World War I had radically altered the political European map, with the defeat of the Central Powers--including Austria - Hungary, Germany, Bulgaria and the Ottoman Empire--and the 1917 Bolshevik seizure of power in Russia, which eventually led to the founding of the Soviet Union . Meanwhile, the victorious Allies of World War I, such as France, Belgium, Italy, Romania and Greece, gained territory, and new nation - states were created out of the collapse of Austria - Hungary and the Ottoman and Russian Empires . </P> <P> To prevent a future world war, the League of Nations was created during the 1919 Paris Peace Conference . The organisation's primary goals were to prevent armed conflict through collective security, military and naval disarmament, and settling international disputes through peaceful negotiations and arbitration . </P> <P> Despite strong pacifist sentiment after World War I, its aftermath still caused irredentist and revanchist nationalism in several European states . These sentiments were especially marked in Germany because of the significant territorial, colonial, and financial losses incurred by the Treaty of Versailles . Under the treaty, Germany lost around 13 percent of its home territory and all of its overseas possessions, while German annexation of other states was prohibited, reparations were imposed, and limits were placed on the size and capability of the country's armed forces . </P> <P> The German Empire was dissolved in the German Revolution of 1918--1919, and a democratic government, later known as the Weimar Republic, was created . The interwar period saw strife between supporters of the new republic and hardline opponents on both the right and left . Italy, as an Entente ally, had made some post-war territorial gains; however, Italian nationalists were angered that the promises made by Britain and France to secure Italian entrance into the war were not fulfilled in the peace settlement . From 1922 to 1925, the Fascist movement led by Benito Mussolini seized power in Italy with a nationalist, totalitarian, and class collaborationist agenda that abolished representative democracy, repressed socialist, left - wing and liberal forces, and pursued an aggressive expansionist foreign policy aimed at making Italy a world power, promising the creation of a "New Roman Empire". </P>

Who was involved in the second world war