The intermittent Germanisation of Prussia was a historical process that resulted in the region’s inclusion in various German states. Originating with the arrival of ethnically German groups in the Baltic region, it progressed sporadically with the development of the Teutonic Order and then much later under the Kingdom of Prussia, which continued to impact the region with germanising policies generally aimed at enhancing state control. Ultimately, attempts at Germanisation peaked as the Prussian state transitioned into the German Empire, which affected Germany's Lithuanian and Polish subjects, only to be halted by the outbreak of the First World War.