The central fact of the geste of Guillaume is the battle of the Archamp or Aliscans, in which perished Guillaume's heroic nephew, Vezian or Vivien, a second Roland.
Guillaume arrived too late to help Vivien, was himself defeated, and returned alone to his wife Guibourc, leaving his knights all dead or prisoners.
This event is related in a Norman-French transcript of an old French chanson de geste, the Chancun de Willame - which only was brought to light in 1901 at the sale of the books of Sir Henry Hope Edwardes - in the Covenant Vivien, a recension of an older French chanson and in Aliscans.
Le Couronnement Looys, already mentioned, Le Charroi de Nimes (12th century) in which Guillaume, who had been forgotten in the distribution of fiefs, enumerates his services to the terrified Louis, and Aliscans (r2th century), with the earlier Chanrun, are among the finest of the French epic poems. The figure of Vivien is among the most heroic elaborated by the trouveres, and the giant Rainouart has more than a touch of Rabelaisian humour.
The idyls were four in number, "Enid," "Vivien" (no longer called "Nimue"), "Elaine" and "Guinevere."
