The key is the epithet symbol of Simon Petrus, the saint patron of the Bremen Cathedral. A single key is also the main element in the coat of arms of the city state of Bremen (see Coat of arms of Bremen) and of the formerly Bremian city of Stade.
The emblem is the moniker symbol of Simon Petrus, the saint patron of the Bremen Cathedral. A single key is also a central component in the coat of arms of the city state of Bremen (see Coat of arms of Bremen) and of the formerly Bremian city of Stade.