The Red Ensign or "Red Duster" is the civil ensign of the United Kingdom of Great Britain and Northern Ireland. It is one of the British ensigns, and it is used either plain or defaced with either a badge or a charge, mostly in the right half.
World War II morale poster
A well used Red Ensign worn on a motorboat
The British Red Ensign being paraded alongside the Australian Red Ensign during the 2007 Anzac Day celebrations in Brisbane, Australia.
In British maritime law and custom, an ensign is the identifying flag flown to designate a British ship, either military or civilian. Such flags display the United Kingdom Union Flag in the canton, with either a red, white or blue field, dependent on whether the vessel is civilian, naval, or in a special category. These are known as the red, white, and blue ensigns respectively.
HMS Endurance carrying HM Queen Elizabeth II flying the Union Jack at the jackstaff and also at the masthead to signify the royal presence.
British Civil Air Ensign in use at Hunsdon Airfield.
The Cenotaph, showing the Royal Air Force and Civil Ensign flanking the Union Jack.
Admiralty Arch is customarily decorated with White Ensigns on state occasions.
