Having espoused the cause of Arthur I, Duke of Brittany, he was captured at Mirebeau (1202), and imprisoned in Corfe Castle. But John of England set him at liberty in 1204, gained him to his side and named him seneschal of Poitou (1205). He was one of those whom John designated on his deathbed for a council of regency to govern the Kingdom of England in the name of new king Henry III of England (1216). In 1227, Savari took part in the rising of the barons of Poitiers and Anjou against the young Louis IX. He enjoyed a certain reputation for his poems in the Langue d'oc.