Eastern Orthodox depictions of Saint George slaying a dragon often include the image of the young maiden who looks on from a distance. The standard iconographic interpretation of the imageicon is that the dragon represents both Satan (Rev. 12:9) and the monster from his life story. The young maiden is the wife of Diocletian, Alexandra. Thus the image, as interpreted through the language of Byzantine iconography, is an image of the martyrdom of the saint.
The episode of St. George and the Dragon was a legend brought back with the Crusaders and retold with the courtly appurtenances belonging to the genre of Romance. The earliest known depiction of the legend is from early eleventh-century Cappadocia (in the iconography of the Eastern Orthodox Church, George had been depicted as a soldier since at least the seventh century); the earliest known surviving narrative text is an eleventh-century Georgian text.
In the fully developed Western version, which developed as part of the Golden Legend, a dragon or crocodile makes its nest at the spring that provides water for the city of "Silene" (perhaps modern Cyrene in Libya or the city of Lydda in the Holy Land, depending on the source). Consequently, the citizens have to dislodge the dragon from its nest for a time, to collect water. To do so, each day they offer the dragon at first a sheep, and if no sheep can be found, then amaiden is the best substitute for one. The victim is chosen by drawing lots. One day, this happens to be the princess. The monarch begs for her life to be spared, but to no avail. She is offered to the dragon, but then Saint George appears on his travels. He faces the dragon, protects himself with the sign of the Cross, slays the dragon, and rescues the princess. The citizens abandon their ancestral paganism and convert to Christianity.
The dragon motif was first combined with the standardised Passio Georgii in Vincent of Beauvais' encyclopaedic Speculum Historiale and then in Jacobus de Voragine's "Golden Legend", which guaranteed its popularity in the later Middle Ages as a literary and pictorial subject.
The parallels with Perseus, Cetus and Andromeda are inescapable. In the allegorical reading, the dragon embodies a suppressed pagan cult. The story has other roots that predate Christianity. Examples such as Sabazios, the sky father, who was usually depicted riding on horseback, and Zeus's defeat of Typhonthe Titan in Greek mythology, along with examples from Germanic and Vedic traditions, have led a number of historians, such as Loomis, to suggest that George is a Christianized version of older deities in Indo-European culture, or at least a suitably Christian substitute for one of them.