[1][2][3][4] The proposed area of the Border Strip comprised up to 30,000 km2 (approximately the size of Belgium), and up to 3 million people were to be ethnically cleansed to make room for German settlers.
The idea of a future "buffer zone" to be cleared of Poles and Jews was discussed officially at highest levels as early as 1914.
[7] In July 1917 the German supreme command under General Ludendorff, as part of the debate and planning regarding the cession of the "border strip" to Germany, specified its own designs in a memorandum.
[1][2][8] Poles living in Prussia, especially in the province of Posen, were to be "encouraged" by unspecified means to move into the German-ruled puppet state of the Kingdom of Poland.
[9] The German government developed and agreed to these plans in March 1918, and in April gained support in the Prussian House of Lords; the plans for this were debated and developed across a wide spectrum of political parties and interested groups such as political scientists, industrialists, and nationalist organisations like the Pan-German League.