Robertian
/rɒˈbəːtɪən/adjective
Of, relating to, or designating the dynasty of Frankish kings founded by the sons of Robert the Strong (d. 866).
noun
A member of the Robertian dynasty.
Origin
Late 19th century; earliest use found in Hilaire Belloc (1870–1953), poet and author. From the name of Robertthe Strong (d. 866), count of Anjou and Blois + -ian. Compare French Robertien, noun and adjective.