Origin: English Folklore
About Dragon of Norton Fitzwarren
During the Iron Age, there was a great battle, which littered the battlefield with bodies.  The Dragon of Norton Fitzwarren spontaneously generated from the corpses, and the ghoul-dragon became a plague by devouring children and destroying crops. 
Then, Fulke Fitzwarren, a thirteenth century knight,  stood up to the beast and slew it after a long, bloody battle.  Fulke later became exiled, but while he adventured abroad he also saved the Duke of Iberia's daughter from a dragon near Carthage. 
A ghastly beast from the battlefield, formed as a terrifying dragon, could be related to an earlier Anglo-Saxon superstition concerning fire and burial. 
However, spontaneous generation of carrion, was a commonly held belief at the time. Because observers would see bugs and other creatures attracted to or hatch out of decomposing animals, many thought that these bodies generated the creatures. Owing to the unpleasant nature of the things found on dead animals, such as maggots, many concluded that the level of potency and disgust of the "born" creatures of carrion related directly to the terror and hatred of the dying creature at the time of death.