Britain and France declare war on the Ottoman Empire
Archduke Franz Ferdinand of Austria and his wife, Sophie, are assassinated by a Bosnian Serb nationalist in Sarajevo.
World War I begins when Austria-Hungary declares war on Serbia
trenches
Germany declares war on Russia, France, and Belgium. Britain declares war on Germany. Austria declares war on Russia. Montenegro declares war on Austria. France declares war on
The First Battle of the Marne begins
The British ocean liner Lusitania is torpedoed by a German U-boat off the southern coast of Ireland. It sinks in just 18 minutes,
The German army initiates the modern era of chemical warfare by launching a chlorine attack on Allied trenches
The British and German fleets meet 60 miles off the coast of Jutland, Denmark, in the war’s only major encounter between the world’s two largest sea powers
The United States declares war on Germany
Germany and the Allies conclude an armistice based largely on Wilson’s Fourteen Points.
