Prussian Centenary Medal (Zentenarmedaille or Kaiser Wilhelm Memorial Medal

Prussian Centenary Medal (Zentenarmedaille or Kaiser Wilhelm Memorial Medal), instituted on March 22, 1897, by Kaiser Wilhelm II to commemorate the 100th birthday of his grandfather, Kaiser Wilhelm I (born March 22, 1797).
The obverse features a right-facing bust of Wilhelm I in military uniform with Pickelhaube helmet, inscribed “WILHELM DER GROSSE DEUTSCHER KAISER KÖNIG VON PREUSSEN” (Wilhelm the Great, German Emperor, King of Prussia).
The reverse shows imperial symbols—a crown, orb, scepter, and sword on a cushion amid laurel and oak leaves—with the inscription “ZUM ANDENKEN AN DEN HUNDERTSTEN GEBURTSTAG DES GROSSEN KAISERS WILHELM I. 22.MAERZ.1797.” (In memory of the 100th birthday of the great Emperor Wilhelm I).
It measures about 40mm in diameter, cast in bronze from captured enemy cannons, and suspends from a 36mm-wide orange ribbon (often called the “Apfelsinenorden” or Orange Order).