In 1914, the Treasury introduced notes for 10/- and £1 to replace gold coins. These circulated until 1928 when they were replaced by Bank of England notes. Irish independence reduced the number of Irish banks issuing sterling notes to five operating in Northern Ireland. The Second World War had a drastic effect on the note production of the Bank of England. Fearful of mass forgery by the Nazis (see Operation Bernhard), all notes for £10 and above ceased production, leaving the bank to issue only 10/-, £1 and £5 notes. Scottish and Northern Irish issues were unaffected, with issues in denominations of £1, £5, £10, £20, £50 and £100.