Since the Iron Cross was issued over several different periods of German history, it was annotated with the year indicating the era in which it was issued. For example, an Iron Cross from World War I bears the year "1914", while the same decoration from World War II is annotated "1939". The reverse of the 1870, 1914 and 1939 series of Iron Crosses have the year "1813" appearing on the lower arm, symbolizing the year the award was created.