Until now, Hubert de Saint Clair has not been given proper recognition as one of the Saint Clair family's important early ancestors, alongside Richard and Bretel. This may be because few historians have been looking for anyone other than William de Saint Clair, either asserting he went to Scotland in 1067, or confusing him with William, one of Hubert's sons.
Hubert, like Bretel, was a tenant of Robert, the count of Mortain, in Dorset and Somerset. According to the Domesday survey in 1086, he held three manors in Dorset: Wintreburne (5 hides), East and West Hemsworth (1 hide), and Witchampton (2 hides). Unfortunately, Wintreburne has not been identified, but the other two can be found close to Blandford Forum. The total extent he held in Dorset was nearly 1000 acres, which was substantial compared to Richard's in East Anglia.
In Somerset, Hubert held Kingstone, which at 4 hides amounted to nearly 500 acres, and in 1130/31, it was part of the barony of Walkern in Hertfordshire, held by Hamo de Saint Clair. This is the strongest indication we have that Hamon was a direct descendant of Hubert. Hamo's only son was Hubert, his name being an additional reason for suspecting that Hubert was Hamo's father. After his grandson Hubert was killed, his daughter Gunnore married William (I) de Lanvalei.
In 1187, the then lord of Kingstone, Oliver de Lanvalei, recognised in the presence of Jocelin, prior of Montacute, at Tintinhull in the full hundred court that 'I Oliver and my men from the vill of Kingstone are obligated to go three times a year to the said hundred of Tintinhull...'
Hamon's brother William referred to his father in letters written in 1135, but unfortunately did not mention his name. At the time, he was donating Villiers, land he held in Normandy, to the abbey of Savigny. If Hubert was Hamo and William's father, which was possible given that they were likely to have been born in the 1090s, then the association of Villiers with the Saint Clair family is likely to have come about through marriage - possibly explained by Hubert's death soon after their birth and his widow marrying Gilbert de Vilers. Indeed, a list of gifts to the Abbey of St. John at Colchester refers to a brother of Hamo de Saint Clair as being Roger de Vilers. It is also clear from later records that land held by Hubert, and later Hamo, in England was the subject of disputes with descendants of the de Vilers family. In 1194-5, Kingstone was held by William de Vilers, and Roger de Vilers held a half fee of Mortain there in 1212.