Although Ireland had the same monarch as England and Wales since Henry Vlll, it had remained a separate country. In 1801, Ireland became unified with England, Scotland and Wales after the Act of Union of 1800. This created the United Kingdom of Great Britain and Ireland was a new version of the official flag, the Union Flag. This is often called the Union Jack. The flag combined crosses associated with England, Scotland and Ireland. It is still used today as the official flag of the UK.
The Union Flag consists of thee crosses:
The cross of St George, patron saint of England, is a Red Cross on a white ground.
The cross of St Andrew, patron saint of Scotland, is a diagonal white cross on a blue ground.
The cross of St Patric, patron saint of Ireland, is a diagonal red coss on a white ground.
There is also an official Walsh flag, which shows a Walsh dragon. The Walsh dragon does not appear on the Union Flag because, when the first Union Flag was created in 1606 from the flags of Scotland and England, the Principality of Wales was already united with England.