World War I, known as "The War to End All Wars," reshaped global politics and society. From 1914 to 1918, major powers clashed in a conflict that introduced new military technologies and tactics, while causing unprecedented destruction and loss of life. The war's causes included nationalism, imperialism, and complex alliances. Key events like the assassination of Archduke Franz Ferdinand sparked a chain reaction, drawing nations into a conflict that spread across continents and transformed the world order.