The Regency Kingdom has been referred to as a puppet state by Norman Davies in Europe: A history (Google Print, p. 910); by Jerzy Lukowski and Hubert Zawadzki in A Concise History of Poland (Google Print, p. 218); by Piotr J. Wroblel in Chronology of Polish History and Nation and History (Google Print, p. 454); and by Raymond Leslie Buell in Poland: Key to Europe (Google Print, p. 68: "The Polish Kingdom... was merely a pawn [of Germany]").