Guillaume Desautels (1529-1599) was a French poet of the sixteenth century associated with La Pléiade.

Guillaume du Vair (7 March 1556 – 3 August 1621) was a French bishop, author, lawyer, Magistrate of the Parliament and Keeper of the Seals of France under French king Louis XIII.

Guillaume Fillastre or Fillâtre was a Burgundian statesman, prelate and patron of arts. He served as a counsellor to Duke Philip the Good and was successively bishop of Verdun (1437–1448), bishop of Toul (1448–1460) and bishop of Tournai (1460–1473). He was also the abbot of Saint-Bertin from 1451 until his death.

Guillaume Grivel was a French writer, legislator, and educator.

Guillaume-Maurice Guizot was a French essayist, translator, professor of literature and civil servant.

Guillaume Levasseur de Beauplan or William le Vasseur de Beauplan was a French-Polish cartographer, engineer and architect.

Guillaume Musso is a French novelist. He is one of the most popular contemporary French authors.

Guillaume Postel was a French linguist, astronomer, Christian Kabbalist, diplomat, polyglot, professor, religious universalist, and writer.

Guillem de Cabestany was a Catalan troubadour from Cabestany in the County of Roussillon. He is often known by his Old Occitan name, Guilhem de Cabestaing, Cabestang, Cabestan, or Cabestanh.

Guillén de Castro y Mateo was a Spanish dramatist of the Spanish Golden Age. He was distinguished member of the "Nocturnos", a Spanish version of the "Academies" in Italy.