 He participated in the so-called "Ladies Parliament" of Nikli in 1261, and enjoyed the complete confidence of William II.In 1267, he ratified the Treaty of Viterbo on behalf of William, sealing a marital pact between Philip, the son of Charles I of Sicily and William's daughter Isabella of Villehardouin and providing for the transfer of the Principality to the Angevins.Leonard died childless ca.