RENARD is the hero of the medieval cycle of beast fables, Roman de Renart. Pierre de St. Cloud was the first French writer to tell stories about Renard the Fox, Ysengrin the Wolf, and Hersint his wife in his Roman de Renart (1180-1185). His possible antecedents were Aesop's Fables and Nivard's Latin poem Ysengrimus (c. 1150). The Roman is divided into Branches: Branch Va--including Renard and Chauntecleer--by Pierre de St. Cloud, and the others by several writers.
Just as Renard, the son of a fox, behaves like a fox, Jason's son Demophon behaves like Jason: they are both false in love, LGW 2448-2449. [Russell]
The name does not appear in The Nun's Priest's Tale, where it might be expected, but only here, medially, LGW 2448.