Rognvald was a supporter of King Harold Harfagr, and assisted him in obtaining the mastery over the other independent Norwegian chiefs, and in establishing himself as King of all Norway. He was Earl of More and Raumsdahl, in Norway, and in 888, he obtained from King Harold,a grant of the Orkney and Shetland Islands, of Scotland. One of his sons, Rolo, conquered Neustria, founded the line of sovereign Dukes of Normandy, and was ancester to William the Conquerer