This map shows a variety of historical data implicitly supporting German expansion in the East: "German national territory before resettlement of the East," "German Eastern Settlement in the 11th -19th century," German "Kulturboden" (see Notes for Penck, 1925, ID #1216), "Eastern border of commercial traffic in the German-language," and "Western and Southern border of the medieval German Empire." The collection includes a number of maps supporting the same point. See Subjects > Between the Wars.