USA HISTORY

Detailed explanation-1: -More than nine million soldiers, sailors and airmen were killed in the First World War. A further five million civilians are estimated to have perished under occupation, bombardment, hunger and disease.

Detailed explanation-2: -Real aggregate Gross Domestic Product (GDP) declined by 9.5 percent over the period 1914 to 1920, while the mobilization of personnel resulted in a 6 percent decline in civilian employment. Meanwhile, although population growth continued during the war years, it was only half that of the prewar rate.

Detailed explanation-3: -Arguably the most profound effect of World War I on African Americans was the acceleration of the multi-decade mass movement of black, southern rural farm laborers northward and westward to cities in search of higher wages in industrial jobs and better social and political opportunities.

Detailed explanation-4: -This increase in militarism helped push the countries involved into war. The immediate cause of World War I that made the aforementioned items come into play (alliances, imperialism, militarism, nationalism) was the assassination of Archduke Franz Ferdinand of Austria-Hungary.