WWII ‘Operation Bernhardt’ good example of a ?50 fake banknote issued by the Nazis in an attempt to destroy the British economy during WWII, under ‘Operation Bernhardt’. The object of the exercise was to flood the British economy with fake banknotes, which had been expertly produced by engravers, many of whom were Jewish and were forced to do it in the concentration camps. In the event British intelligence intercepted the plot and only one ?5 was paid out. However, the aftermath of the attempt prompted the Government to require anyone obtaining a genuine ?5 note from the bank to have to sign for it- and indeed no British banknote with higher value than ?5 was issued until 1971.