Between World War One and Two, Germany experienced several changes in government: from an emperor to democracy to the rise of a new dictator, a Führer. Indeed, it’s this last leader, Adolf Hitler, who directly began the second of the twentieth century’s two great wars.
The German Revolution of 1918-19
Faced with defeat in the First World War, the military leaders of Imperial Germany convinced themselves that a new civilian government would do two things: take the blame for the loss, and persuade the soon to be winners of the war to demand only a moderate punishment. The socialist SDP was invited to form a government and they pursued a moderate course, but as Germany began to fracture under pressure so calls for a full-fledged revolution were demanded by the extreme left. Whether Germany really did experience a revolution in 1918-19, or whether that was defeated is debated.