Why is British flag red white and blue?

[admin]

The Union Jack is red, white and blue because it takes the colours from Ireland, Scotland and England flags. ... It is not included because at the time the Union Jack was created in 1801, Wales was a part of England.

[Albert Davis]

They're the colours of the union jack, the flag the United Kingdom has presented to the world since 1801. It features the crosses of three patron saints - George (England), Andrew (Scotland) and Patrick (Ireland - although since 1921 only Northern Ireland has been part of the UK).