History of Germany during World War I
In November 1918, with internal revolution, a stalemated war, Bulgaria and the Ottoman Empire suing for peace, Austria-Hungary falling apart from multiple ethnic tensions, and pressure from the German high command, the Kaiser and all German ruling princes abdicated. On 9 November 1918, the Social Democrat Philipp Scheidemann proclaimed a Republic, in cooperation with the business and middle classes, not the revolting workers. The new government led by the German Social Democrats called for and received an armistice on 11 November 1918; in practice it was a surrender, and the Allies kept up the food blockade to guarantee an upper hand. The war was over; the history books closed on the German Empire. It was succeeded by the democratic, yet flawed, Weimar Republic.
Perpetual Diet of Regensburg
The last action of the Diet, on 25 March 1803, was the passage of the German Mediatisation, which reorganized and secularized the Empire. Following the approval of that final constitutional document, the Diet never met again and its existence ended with the fall of the Empire in 1806.