The kingdom of Prussia was in existence from 1701 to 1918.
The Kingdom of Prussia ( Königreich Preußen ) was a German kingdom that constituted the state of Prussia between 1701 and 1918 and included parts of present-day Germany , Poland , Russia , Lithuania , Denmark , Belgium and the Czech Republic . Prussia . In November 1918 , the monarchies were abolished and the nobility lost its political power during the German Revolution of 1918 -- 19 . The union of Brandenburg and the Duchy of Prussia in 1618 led to the proclamation of the Kingdom of Prussia in 1701 . The Kingdom ended in 1918 .