Background
He married Helena Angelina Komnene, daughter of John I Doukas, ruler of Thessaly, securing a military alliance with him.
He married Helena Angelina Komnene, daughter of John I Doukas, ruler of Thessaly, securing a military alliance with him.
William reversed the territorial losses of his brother"s reign, extending his control over Lamia and Gardiki. In 1285, while Charles II of Naples, nominal prince of Achaea, was imprisoned, Robert of Artois, regent of the kingdom, named William bailiff and vicar-general of Achaea. He was then the most powerful baron in Frankish Greece.
In 1286, he arbitrated the succession of the March of Bodonitsa following the death of Isabella Pallavicini.
William"s rule was peaceful, but short, as he died two years after assuming power in Achaea(1287).
He built the castle of Dimatra to defend Messenia from the Byzantine Empire.