He bore on his shield the red lion rampant becoming the undisputed premier subject of the kingdom. After his death in 1128, the men of Moray made a few unsuccessful attempts to claim the throne whilst Clan Duff was to give its allegiances to Queen Margaret.
The male line of Earls failed in 1353 and passed to Robert Stewart, later Duke of Albany and Regent of Scotland. In 1425 the earldom passed to the crown and the clan lost their great rank.
A Fife title was to return with William Duff and the Earl of Fife and Viscount Madcap in 1759.
Later Alexander, the sixth Earl of Fife, married the Princess Royal, HRH Louise (daughter of King Edward VII).
The direct line of the ancient house, continued in Wemyss whilst in the northern territories, families of Clan Duff emerged in historical record with no proof of royal descent.