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Flag of England -

The Union Flag combines the crosses of three countries. The flag of England, a red cross on a white background, is known as St George's Cross. St George has been the patron saint of England since the 1270s.

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Flag of Scotland -

The flag of Scotland is the white saltire of St Andrew, patron saint of Scotland since 1320.

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Saltire of St Patrick -

This is the red saltire of St Patrick, the third component of the Union Flag. It represents Ireland, although since 1921 only Northern Ireland has been part of the United Kingdom. While revered as a saint since the 6th century, Patrick was never formally canonized. Since the 1630s, St Patrick's Day has been celebrated annually on March 17, the supposed date of his death. Image: Hoshie and others

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Union Flag -

The Union Flag, the national flag of the United Kingdom, is therefore named for the three countries united under one Sovereign—England, Scotland, and the historic province of Northern Ireland. The Union Flag as we know it today was formally adopted in 1801, and is commonly called the Union Jack. But why isn't Wales represented on the flag?

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Welsh dragon -

The Welsh dragon does not appear on the Union Flag. This is because when the first Union Flag was created in 1606, Wales was already united with England by the 1536 Act of Union, signed by Henry VIII, thus invalidating the nation as a separate principality.

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The pre-1801 Union Flag -

This is what the flag of Great Britain looked like before 1800. Missing is the red saltire of St Patrick, which wasn't incorporated until the Acts of Union 1800. The origins of this earlier flag date back to 1606, and King James VI and I. Image: Hoshie

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James VI and I (1566–1625) -

In 1603, James VI of Scotland inherited the Kingdom of England (and the newly-created client state, the Kingdom of Ireland) as James I, thereby uniting the crowns in a personal union. While the three kingdoms remained separate states, the king nevertheless ordered a new flag to represent this regal bond. However, the red saltire was only added to the British flag to form the Union Flag after the 1800 Act of Union, which officially joined the Kingdom of Ireland with the Kingdom of Great Britain.

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Pre-union -

In this 1746 engraving, the pre-union flag of Great Britain is clearly discernible hoisted over the Church of St Dunstan and All Saints in Stepney, London.

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Pre-union -

Similarly, the earlier flag of Great Britain can be seen fluttering over the Tower of London in this 1776 engraving.

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Acts of Union 1800 -

When the Union Flag was officially adopted in 1801, it became a royal flag. It was ordered to be flown on all the King's forts and castles, including Windsor (pictured), and at sea on civil and military ships of both England and Scotland, but not elsewhere.

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Royal Standard -

This edict was reversed with the introduction of the Royal Standard during the reign of Queen Victoria. The Royal Standard is flown at royal residences across the land only when the sovereign is present.

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In residence -

In fact, the Union Flag is replaced by the Royal Standard when the Queen is in residence in one of the Royal Palaces, such as Windsor Castle (pictured).

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Royal Banner of Scotland -

The Scottish equivalent of the Royal Standard is the Royal Banner of Scotland, more commonly known as the Lion Rampant of Scotland.

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Balmoral Castle -

Confusingly, the Royal Banner of Scotland is flown at the Palace of Holyroodhouse and Balmoral when the monarch is not in residence.

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Buckingham Palace -

Conversely in England, the Union Flag is flown above Buckingham Palace, Windsor Castle, and Sandringham when the Queen is not at home.

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The origin of "Jack" -

Debate surrounds the origin of the word "Jack." In common parlance, a jack is a flag flown from a short jack staff at the bow (front) of a vessel.  While the name "Union" first appeared in the 1600s, there are various theories as to how it became known as the "Union Jack."

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Union Jack -

Sometime during the 1670s, the British flag became formally known as the Union Jack when mounted on a warship and the ship was not in harbor. At the same time, the British flag was referred to as the "Union Flag" on land. By the 19th century, the national flag was commonly being called the Union Jack.

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Houses of Parliament -

Furthermore, the Union Jack was eventually sanctioned by the British government for official use, and confirmed as the national flag by Parliament.

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Commonwealth nations -

Besides the United Kingdom, four Commonwealth nations have the Union Jack on their national flag: Australia, New Zealand, Tuvalu, and Fiji. Canada dropped the Union Flag in 1965 after adopting a new national flag. Pictured is the old Canadian Red Ensign, used from 1868 to 1921. All British Overseas Territories fly the Union Jack.

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Flag of Australia -

Admiral Arthur Phillip (1738–1814) was a Royal Navy officer who became the founding governor of the Colony of New South Wales in 1788. He was the first to raise the Union Jack in Australia. Today the flag is flown beside Customs House in Loftus Street, Sydney, to mark the approximate location at which the ceremony took place.

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Flag of New Zealand -

New Zealand incorporated the Union Jack into its national flag in 1902. The four five-pointed red stars with white borders on the fly represent the Southern Cross.

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Grand Union Flag -

The Grand Union Flag is considered to be the first national flag of the United States of America. A colonial banner of sorts, it has 13 alternating red and white stripes, representative of the Thirteen Colonies, and features the flag of the Kingdom of Great Britain, of which the colonies had been subjects. It was relinquished on June 14, 1777 in favor of the Stars and Stripes.

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Flag of Hawaii -

The Flag of Hawaii is the only US state flag to include a foreign country's national flag. The inclusion of the Union Jack is a mark of the British Royal Navy's historical relations with the Hawaiian Kingdom.

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Half-mast -

The practice of flying the Union Jack at half-mast dates back tp the 17th century. It's carried out upon the death of the sovereign, other members of the royal family, foreign rulers, and other VIPs and dignitaries by command of the monarch. Pictured is the Union Jack at half-mast at the Tower of London on April 9, 2021, after the Queen had announced the death His Royal Highness Prince Philip, Duke of Edinburgh.

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The Union Jack in popular culture -

The Beatles announce their arrival in the United States in 1964 with a Union Jack. The fab Four were about to embark on their first tour of America.

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The Who -

Pete Townshend of The Who tunes up in great British style while on stage in the United States in 1967.

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David Bowie -

David Bowie strikes a patriotic pose on stage at the Phoenix Festival held near Stratford-Upon Avon, England, on July 18, 1996.

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Spice Girls -

The Spice Girls in full voice at the 1997 Brit Awards, with band member Geri Halliwell flying the flag for the nation.

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The Queen and the flag -

Queen Elizabeth II and Prince Philip, Duke of Edinburgh seen in 2011, met by a sea of Union Jack flags during a Royal Tour.

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Having the cake and eating it -

Cupcakes themed with icing depicting the Union Jack, the US flag, and stars and crowns to mark the wedding of Prince Harry to Meghan Markle. 

Sources (The Royal Family) (Britannica) (BBC) (Smithsonian Magazine)

See also: Star-spangled facts about the American flag

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