Union Jack Union Jack The Union Jack, or Union Flag, is the national flag of the United Kingdom. The flag also has an official or semi-official status in some other Commonwealth realms: for example, it is a ceremonial flag in Canada by parliamentary resolution, and known there as the Royal Union Flag. Further, it is used as an official flag in some of the smaller British overseas territories. The Union Flag also appears in the canton (upper left-hand quarter) of the flags of several nations and territories that are former British possessions or dominions, as well as the state flag of Hawaii.
Union Jack maritime bow flag. By 1627 a small Union Jack was commonly flown in this position. One theory goes that for some years it would have been called just the "Jack", or "Jack flag", or the "King's Jack", but by 1674, while formally referred to as "His Majesty's Jack", it was commonly called the "Union Jack", and this was officially acknowledged. Amongst the proclamations issued by King George III at the time of the Union of 1801 was a proclamation concerning flags at sea, which repeatedly referred to "Ensigns, Flags, Jacks, and Pendants" and forbade merchant vessels from wearing "Our Jack,