-
Archduke Assassination
Archduke Franz Ferdinand is assassinated in Sarajevo. His death is the event that sparks World War I. -
Russia Mobilizes
Russia mobilizes its vast army to intervene against Austria-Hungary in favor of its ally, Serbia. This move starts a chain reaction that leads to the mobilization of the rest of the European Great Powers, and inevitably to the outbreak of hostilities. -
World War I Begins
Germany invades Belgium, beginning World War I. -
Germans Fire
The Germans fire shells filled with chlorine gas at Allied lines. This is the first time that large amounts of gas are used in battle, and the result is the near-collapse of the French lines. However, the Germans are unable to take advantage of the breach.