The term German Empire (Deutsches Kaiserreich) commonly refers to Germany from its foundation as a unified nation-state on 18 January 1871 until the abdication of its last Kaiser, Wilhelm II, was proclaimed on 9 November 1918.

In total, there were 22 federal princes of the German Empire and additionally three republican heads of state and the steward of the imperial territory ruled by Alsace-Lorraine.

The list does not include local rulers in German colonies such as Yuhi V of Rwanda, Mwambutsa IV of Burundi and Aweida of Nauru.

The next day, the Emperor and King of Prussia Wilhelm II, went into exile in the Netherlands, and his abdication (which he would not officially confirm until 28 November, see below) was announced by his Chancellor and Prussian Minister President Maximilian of Baden.

Neither proclamation of the republic was constitutional, and the political situation remained chaotic for several more months, with a short civil war between radical leftist revolutionaries and the more moderate post-imperial social democrat government that would emerge victorious and form the Weimar Republic.

Nevertheless, the proclamations and Wilhelm II's abdication triggered a powerful domino effect: the same day a number of other princes stepped down, and within a week most monarchs in Germany had followed suit.