The Kingdom of Poland (Polish: Królestwo Polskie), also known informally as the Regency Kingdom of Poland (Polish: Królestwo Regencyjne), was a proposed puppet state of the German Empire during World War I. The decision to propose the restoration of Poland after a century of partitions was taken up by the German policymakers in an attempt to legitimize further imperial omnipresence in the occupied territories. The plan was followed by the German propaganda pamphlet campaign delivered to the Poles in 1915, claiming that the German soldiers were arriving as liberators to free Poland from subjugation by Russia.

A draft constitution was proposed in 1917. The German government used punitive threats to force Polish landowners living in the German-occupied Baltic states to relocate and sell their Baltic property to the Germans in exchange for the entry to Poland. Parallel efforts were made to remove Poles from Polish territories of the Prussian Partition.

Following the Armistice of 11 November 1918 signed by the Allies with imperial Germany, which ended World War I, the area became part of the nascent Second Polish Republic.

Before the onset of war in 1914, for the purposes of securing Germany's eastern border against the Russian imperial army, Theobald von Bethmann-Hollweg, the German chancellor, decided on the annexation of a specific strip of land from Congress Poland, known later on as the Polish Border Strip. In order to avoid adding the Polish population there to the population of imperial Germany, it was proposed that the Poles would be moved to a proposed new Polish state further east, while the strip would be resettled with the Germans.

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