thumb|Detail of the frontispiece of a French edition of Guillaume de Palerne ()
Guillaume de Palerne or in modern spelling Palerme ("William of Palerne" or "Palermo") is a French romance poem, later translated into Middle English where it is also known as William and the Werewolf. The French verse romance is thought to have been composed anywhere from the late 12th to late 13th century (cf. ). The verse version in French survives in a single 13th century manuscript (l'Arsenal 6565 olim 178).
The prose version of the French romance (created before 1535) went through early printed editions. The edition from of Paris passed through several post-incunabula editions (c. 1550–1590?), into the 17th century.
The English poem in alliterative verse, commissioned by Humphrey de Bohun, 6th Earl of Hereford, was written (or more precisely between 1335/6 and 1361 Past editors and commentators (based on earlier death date of the countess<!--cf. Dunn apud Williams below-->) had ascribed composition before