The United Kingdom of Great Britain and Northern Ireland uses as its national flag the royal banner known as the Union Flag or, popularly, Union Jack. The current design of the Union Flag dates from the union of Ireland and Great Britain in 1801. It consists of the red cross of Saint George (patron saint of England), edged in white, superimposed on the Cross of St Patrick (patron saint of Ireland), which are superimposed on the Saltire of Saint Andrew (patron saint of Scotland).
It retains an official or semi-official status in some Commonwealth Realms, for example in Canada where it is known as the Royal Union Flag. The current design dates from the Union of Great Britain and Ireland in 1801.