Dragon's Castle Buttons

The most famous dragons in Norse mythology and Germanic mythology are Jormungand, a form of cobra so big that the earth-disc can be encircled by it; the dragon encountered by Beowulf; and Fafnir, who Siegfried killed. Fafnir turned into a dragon because of his greed. Many European stories of dragons have them guarding a treasure hoard. Fafnir's and Beowulf's dragons guarded earthen mounds full of ancient treasure. The treasure was cursed and brought ill to those who later possessed it.
Dragons in the emblem books popular from late medieval times through the 17th century often represent the dragon as an emblem of greed. (some quotes are needed) The prevalence of dragons in European heraldry demonstrates that there is more to the dragon than greed.

Although we almost universally associate dragons with fire today, in medieval legend, they were often associated with water. They guarded springs or lived near or underwater. Other European legends about dragons include "Saint George and the Dragon," in which a brave knight defeats a dragon holding a princess captive. This legend may be a Christianized version of the myth of Perseus or the mounted Phrygian god Sabazios vanquishing the Chthonic serpent, but its origins are obscure. Saint George is the Patron Saint of England. Meanwhile, across the border, a red dragon is represented on the Welsh flag. Due to this clash of symbolism, few George and the Dragon pubs exist in Wales.