What caused World War 2 and World War 1 to start?

Answer 1

Both of the world wars had multiple causes. In the case of WW I there were two very big alliances in Europe, competing for domination of Europe and the world (at that period in history, most of the world was in some way colonized by Europe). There were also separatist movements which were a destabilizing influence; the direct cause of WW I was the assassination of the Archduke Franz Ferdinand of Austro-Hungary by a Serbian separatist. There was also a long-standing territorial dispute between France and Germany over the province of Alsace-Lorraine, which was part of France prior to WW I and which Germany wished to seize from France. Those were the main causes of WW I. The main cause of WW II was simply that Germany and its allies were not satisfied with the results of WW I and wanted a rematch. Economic problems resulting from the Great Depression were making everybody very bellicose as well. People thought that they could solve their problems through war. And actually, WW II did provide a great economic stimulus. But the cost was extremely high.