Original: The Knight's Cross of the Iron Cross (German language: Ritterkreuz des Eisernen Kreuzes, often simply Ritterkreuz) was a grade of the 1939 version of the 1813 created Iron Cross (Eisernes Kreuz).
Simplified: The Knight's Cross of the Iron Cross (German language: Ritterkreuz des Eisernen Kreuzes, often just Ritterkreuz) was a level of the Iron Cross.