The Bank of England was established in 1694 as one of the oldest banks of the world. It has been functioning as the central bank of England since 1946. The 8th oldest bank of the world has become the model for the other central banks over the world.
Adam Smith, the great economist and philosopher has been featured by two different banks in the UK by printing his portrait on the banknotes. That was to commemorate his contribution to the modern economy. On 13 March 2007, the current £20 note of UK was first introduced featuring Adam Smith as the first ever Scotsman to be featured on an English banknote. However, his portrait has been appearing on the £50 note issued by Clydesdale Bank in Scotland since 1981.
Source: Wikipedia