Guglielmo II da Verona (died 1273/1275) was a Lombard noble from the triarchy of Negroponte (Euboea), considered by earlier historians as a triarch and a marshal of the principality of Achaea in Frankish Greece.
He was the second[1] son of Guglielmo I da Verona, ruler of the southern third ("triarchy") of Euboea.[2]
According to earlier historians following K. Hopf, he succeeded to this position upon his father's death in 1263/6. He was also thought to have become Baron of Passavant and marshal in the Principality of Achaea from an hypothetical marriage to Margaret de Neuilly,[3] because he was improperly called "marshal" in Sanudo's Istoria di Romania.[4] These views have been challenged by Raymond-Joseph Loenertz in the 1960s.
He married Catherine, a niece of William II of Villehardouin,[5] with whom he had no known child.
Guglielmo was killed in the Battle of Demetrias, which took place either in 1273 or in 1275 in the area of modern Volos.[6][7]