The Flag of Wales (Welsh: Baner Cymru or Y Ddraig Goch, meaning “The Red Dragon”) consists of a red dragon passant on a green and white field.
As with many heraldic charges, the exact representation of the dragon is not standardised and many renderings exist.
The Welsh flag incorporates the Red Dragon of Cadwaladr, King of Gwynedd, along with the Tudor colours of green and white. It was used by Henry VII at the Battle of Bosworth Field in 1485 after which it was carried in state to St Paul’s Cathedral. The red dragon was then included in the Tudor royal arms to signify their Welsh descent. It was officially recognised as the Welsh national flag in 1959.
Wales and Bhutan are the only countries to have a dragon as a major design element on their flag, though the Chinese flag also featured a dragon during the Qing Dynasty, and a dragon appears on the badge of the George Cross on the flag of Malta. Wikipedia