The Gniezno issues
Fischer 71-72 | Michel 135-136 | Scott 77-78 | Year of issue 1919 | Pre-war Poland
These are Germania stamps with overprints, issued from Gniezno.
Germania issues overprinted with a large 5 and 10
Gniezno is a town in Poland.
Germania issues are a series of German stamps, released between 1900-1921, with the portrait of the Wagnerian opera star Anna von Stratz-Fuhring, representing the German empire.
Deutches Reich = German Empire.
Germania issues (muenster.de)
Germania issues (datanet.hu)
Scans provided by Michael Lenke