St. George is a martyr, but more famously if less historically certainly a dragonslayer.
There are several stories about George fighting dragons, but in the Western version, a dragon or crocodile made its nest at a spring that provided water to Silene, believed to be modern-day Lcyrene in Libya.
The people were unable to collect water and so attempted to remove the dragon from its nest on several ocassions. It would temporarily leave its nest when they offered it a sheep each day, until the sheep disappeared and the people were distraught.
This was when they decided that a maiden would be just as effective as sending a sheep. The townspeople chose the victim by drawing straws. This continued until one day the princess' straw was drawn.
The monarch begged for her to be spared but the people would not have it. She was offered to the dragon, but before she could be devoured, George appeared. He faced the dragon, protected himself with the sign of the Cross, and slayed the dragon.
After saving the town, the citizens abandoned their paganism and were all converted to Christianity.