The major historical event that started in 1914 and reshaped nations across the world was World War I, which lasted until 1918. Triggered by the assassination of Archduke Franz Ferdinand of Austria, the war involved numerous global powers divided into two main alliances: the Allies and the Central Powers. The war was characterized by trench warfare and unprecedented levels of destruction, leading to significant military and civilian casualties. The outcome resulted in the collapse of empires, redrawn borders, and the Treaty of Versailles, which imposed heavy reparations on Germany. The war fundamentally altered the political landscape, setting the stage for social changes and the eventual rise of fascism leading to World War II.