Postcards / postage-stamps issued for the 1st anniversary of establishing of General Government (Generalgouvernement, Generalne Gubernatorstwo). 
 
The small series of 3 stamps  was one of the first series of stamps issued by Germans for the use in General Government. They were issued on 28th of October 1940 to commemorate the first anniversary of establishing the General Government (administrative unit ruling occupied Poland). 
These beautiful stamps were designed by a German painter and artist Otto Engelhardt-Kyffhäuser. He was an SA, SS and NSDAP member, which certainly helped him get some business. 
 
If you are interested in the post-stamps only, check here.