Dear Max Guldberg, Heidenreich, Heydenreich or Heydenryke are old farmer families of the Krempermarsch area since 500 years. If you want to find old documents of the family you must look for old estate contracts in the Schleswig-Holstein Archives of Schleswig. An old beautiful Heydenreich farmhouse of 1711 was rebuilt in the farmhouse museum of Molfsee near Kiel. Klaus Timm