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.
Jack (flag) or confederated states have in many cases adopted a jack representing their national union. The best known is the Union Jack of the United Kingdom's Royal Navy, composed in 1606 by joining together the flags of England and Scotland. When the Kingdom of Ireland merged with Great Britain in 1801, a red saltire (St Patrick's Cross) was added to form the present Union Flag. The design of the British Union Jack probably inspired later jacks of other nations, e.g. Russia and the Union Jack of Norway and Sweden. The Russian jack in its turn inspired the jacks of Bulgaria, Estonia