Research Notes:
Stephen of Penthièvre (1058/62- 21 April 1136), a Breton noble, was a younger son of Odo, Count of Penthièvre and Agnes of Cornouaille, sister of Hoel II, Duke of Brittany. In 1093, he succeeded to the title of Count of Tréguier; in 1098, he succeeded his brother Alain as Lord of Richmond in Yorkshire, England. In English documents he is called Count Stephen of Brittany, Lord of Richmond.