Map showing the w:Duchy of Prussia, at an indeterminable date. Place names inside the Duchy are given in German, as are Elbing and Marienburg. Other names are modern.
  Territory of the Duchy of Prussia
  Territory of the Kingdom of Poland before the Union of Lublin
  Territory of the Grand Duchy of Lithuania before the Union of Lublin
  Polish-Lithuanian border before the Union of Lublin
  Polish-Lithuanian border after the Union of Lublin
Own work
Grandiose, data from (2001) Lietuvos istorijos atlasas, Vilnius: Vaga, pp. 16-17.