This document provides an overview of World War I, including its causes, major events, and aftermath. It discusses the alliance systems and militarism that divided Europe prior to the war. The assassination of Archduke Franz Ferdinand sparked the initial conflict. Both sides suffered immense casualties, especially along the brutal Western Front. New military technologies, such as tanks and airplanes, emerged. The war also had devastating impacts across the global empires and led to over 9 million deaths when it ended in 1918.