Flags of Great Britain: the flag of Cornwall (since the 19th century) together with the flags of Scotland and of England (since the Middle Ages) and the flag of Wales (since 1959).
This file was derived from:

 Flag of Cornwall.svg
Flag of England.svg
Flag of Scotland.svg
Flag of Wales.svg
Own work based on: Flag of Cornwall.svg: , Flag of England.svg: , Flag of Scotland.svg:   and Flag of Wales.svg: