He was the son of Godefroi I of Challant, viscount of Aosta, and Beatrice of Geneva.
He inherited from his paternal uncle the titles of Aosta and the fiefs of Challant, Graines, Ussel, Fénis and Saint-Marcel.
In 1295 he renounced to the title of viscount of Aosta, which thus returned to the counts of Savoy, receiving in exchange the remaining lands of Montjovet.
During his c. 50 years of countship, he was a faithful ally of Amadeus V of Savoy, but kept good relationships with the latter's main enemies, the Marquisses of Montferrat.
In 1280 he intervened with Amadeus to obtain the releasing of William VII of Montferrat.