aka Orgar. Ealdorman of Devon (The concise dictionary of national biography. Part 1 : from the beginnings till 1900. London : Oxford University Press, 1969, pg. 978). Paul B. McBride web site speculates he may be the son of Alpsius, Duke of Devon.
According to Gaimar, Ordgar was the son of an ealdorman, and owned land in every parish from Exeter in Devon to Frome in Somerset. He married an unknown lady of royal birth, by whom he had a daughter Ælfthryth. The Oxford Dictionary of National Biography draws a conclusion that Ordgar was "clearly a figure of some importance" to have secured such a match.[1] King Edgar determined on marrying Ælfthryth and to this end he sent Æthelwald, Ealdorman of East Anglia as his agent to woo her. On arrival Æthelwald found her in company with her father Ordgar, whom she completely controlled by her personality, playing at chess, which they had learned from the Danes.[4] Æthelwald instead took Ælfthryth for his own wife and married her in about 956.[4]
Æthelwald died in 962, and Dunstan suspected that he was murdered by his wife Ælfthryth who thereafter, according to Dunstan, seduced King Edgar and murdered his son Prince Edward the Martyr in order to pave the way for the crowning of her son Æthelred as king. It is however certain that, under whatever actual circumstances, Ælfthryth became King Edgar's third wife in 964 and in the same year her father Ordgar was created Ealdorman. The ODNB supposes that Ordgar from the time of his daughter's royal marriage until 970 was one of Edgar's closest advisors, by virtue of his being named as witness on almost all charters issued by King Edgar during the period (wikipedia.com)