Is it a pennant or Kriegsflagge (German naval ensign)?

Naval flags are made in various sizes to suit the size of the ship which is flying them. A U-boat flag would look rather insignificant on a ship the size of the Tirpitz and a battleship flag would probably cover quite a bit of a small vessel such as a submarine.

There were many around post-war but I doubt if they had the name of the vessel they were issued to printed on them probably just official markings that identified them as belonging to the Kriegsmarine. Flags do not need a rocket scientist to make them and it is not difficult, knowing the right techniques,to age them. Then with a suitable rubber stamp and some permanant ink to stamp whatever is necessary on them. God forbid but even a White Ensign could be so marked to look as though it had been issued by the Kriegsmarine.

MPC

PS Many materials like leather, paper, wood, cloth, metals etc. can be aged quite easily. It is possible to buy a genuine piece of wood from HMS Victory but when all those small pieces are sold what is left?

'Caveat emptor'