WWI Occupation - Poland
1916 / 1917 Overprints
This set was issued on 1 August 1916, and saw a switch to an overprint of “Gen-Gouv. Warschau”.
1916 / 1917 Overprints
This set was issued on 1 August 1916, and saw a switch to an overprint of “Gen-Gouv. Warschau”.