Third Reich 50 Years of German Heligoland MiNr. 750 This stamp was issued on 9 August 1940 to commemorate 50 years of German control over Heligoland. Set Date(s) 9 August 1940 Watermark(s) None Album Page(s) 50 Years of German Heligoland MiNr. 750 This stamp was issued on 9 August 1940 to commemorate 50 years of German control over Heligoland. Set Date(s) 9 August 1940 Watermark(s) None Album Page(s)