National flag

A national flag is a flag that symbolizes a country. The flag is flown by the government, but usually can also be flown by citizens of the country.

Historically, flags originate as military standards, used as field signs. The practice of flying flags indicating the country of origin outside of the context of warfare became common with the maritime flag, introduced during the age of sail, in the early 17th century. The origins of the Union Jack flag date back to 1603, when James VI of Scotland inherited the English and Irish thrones (as James I), thereby uniting the crowns of England, Scotland and Ireland in a personal union (which remained separate states). On 12 April 1606, a new flag to represent this regal union between England and Scotland was specified in a royal decree, according to which the flag of England (a red cross on a white background, known as St George's Cross), and the flag of Scotland (a white saltire on a blue background, known as the Saltire or St Andrew's Cross), would be joined together, forming the flag of Great Britain and first Union Flag.

With the emergence of nationalist sentiment from the late 18th century the desire was felt to display national flags also in civilian contexts, notably the US flag, in origin adopted as a naval ensign in 1777, which after the American Revolution began to be displayed as a generic symbol of the United States, and the French Tricolore which became a symbol of the Republic in the 1790s.

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