 As he was returning, he joined marquesses John II of Montferrat and Thomas II of Saluzzo in their fight against Robert's successor, Queen Joanna I of Naples, who was supported by the Savoyards.When Pope Clement VI brought the two sides to negotiations, the terms included the possibility of Humbert marrying Bianca of Savoy, though this did not reach agreement.The planned sale to the pope falling through, Humbert finally succeeded in completing a sale to King Philip VI of France in 1349 for 400,000 "écus" and an annual pension.