Heraldry
In England, to this day, a rampant red dragon (clutching a mace) is the heraldic symbol of the County of Somerset. The county once formed part of the early-medieval Anglo-Saxon kingdom of Wessex in western England, which too bore a dragon or wyvern (a two-legged as opposed to a four-legged dragon) as a symbol. The Wessex beast is usually colored gold in illustrations.
According to the writer on heraldry Arthur Charles Fox-Davies, the red dragon of Wales originated with the standard of the 7th century king Cadwaladr, and was used as a supporter by the Tudor dynasty (who were of Welsh origin). Queen Elizabeth, however, preferring gold, changed the royal mantle and the dragon supporter from red to gold, and some Welsh scholars still hold that the dragon of Wales is properly ruddy gold rather than gules. There may be some doubt of the Welsh origin of the dragon supporter of the Royal arms, but it certainly was used by King Henry III.
The Welsh flag is parti per fess Argent and Vert; a dragon Gules passant. Welsh rugby teams include the Newport Gwent Dragons and the Cardiff City Blue Dragons.
King Peter IV of Aragon used a dragon on his helmet to show that he was the king of Aragon, as a heraldic pun (Rei d'Aragón, dragón).
Read more about this topic: European Dragon