- Period:
- Second World War (1939-1945)
- Rank:
- Oberleutnant (1st Lieutenant)
- Unit:
- stellvertretender Führer II. / Grenadier-Regiment 105
- Awarded on:
- February 18th, 1945
Karl Zimmer was awarded the Knight's Cross for actions at Schmerinka, Soviet Union, for leading his Kompanie in house-to-house fighting that re-took a Russian position.