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The flag of the United Kingdom combines the cross of St. George (a red cross on a white background) with the cross of St. Andrew. This combination of 2 crosses was created in 1801 following the union of England and Scotland. It forms the flag we know today as the "Union Jack".
However, the British ships that ply the oceans do not fly this flag at the stern. They fly the Red Ensign, a red flag with the Union Jack in one corner. But curiously, this flag is often on a red background, but sometimes with blue or even white. Where does this change come from, and what do these colors mean?
Red Ensign, the most popular
Since 1864, the Red Ensign has been used to signal English merchant ships, and by declination pleasure craft. It is therefore the most common flag worn by the British.
The Blue Ensign
The Blue Ensign is reserved for ships in public service or commanded by a reservist officer of the Royal Navy (England's maritime armed force). This particular ensign can be found on English merchant ships commanded and crewed by a number of retired or reservist Royal Navy officers. More anecdotally, yachts belonging to members of certain old English clubs, such as the Royal Northern & Clyde Yacht Club, are authorized to fly this flag.
The White Ensign
The White Ensign (also known as Saint George's Ensign) is the flag of the Royal Navy. It is worn on Royal Navy ships and at Royal Navy-operated naval bases. The Royal Yacht Squadron and ships accompanying the King also fly it.
A little logo on the Red Ensign
Occasionally, the Red Ensign features a small additional design in the red section. These are the flags of Guernsey, the Isle of Man or Bermuda.
