The revolution in November 1918 led in Württemberg, like everywhere in Germany, to the end of the monarchy. King William II left Stuttgart on 9 November, shortly after a revolutionary crowd had stormed his residence, the Wilhelm Palais and flown a red flag above the building. On the very same day the demonstrators were also able to seize some of Stuttgart's barracks, where parts of the garrisons openly joined them. Rau took active part in the events in Stuttgart's streets on this and the following day.