36mm wide circular bronze medal with medallion suspension; the face with a helmeted standing male, his left arm outstretched holding an upright lance, swirling standards beyond, dated ‘17-31 OCT 1914’, signed ‘EMILE VLOORS’ (for the Belgian artist and engraver, 1871-1952), the suspension medallion inscribed ‘YSER’; the reverse with a seated lion wounded in the flank, a battle field beyond, inscribed ‘YSER’ below, the suspension medallion bearing the crowned cipher of King Albert I; on original ribbon mounted for wear in the Belgian style.

The medal was instituted on 18 October 1918 and awarded to those who between 17 and 31 October 1914 resisted the German advance at the River Yser where the Belgian army took the full brunt of a major German attack and suffered 60,000 casualties, a third of its strength. The battle was crucial in holding for the Allies the ports of Dunkirk, Calais and Boulogne.