meschin was the brother of ranulf le meschin, the earl of chester. they were the sons of ranulf de briquessart, the viscount of the bessin, and his wife, matilda, the daughter of richard le goz, viscount of avranches. the boys were also nephews of hugh d'avranches, who was earl of chester. there was also an older brother, richard, who died young, and a sister, who married robert de grandmesnil. meschin went on the first crusade and was present at the siege of nicaea in 1097.