Dictionary of National Biography, 1885-1900/Olaf Godfreyson
OLAF Godfreyson (d. 941), leader of the Ostmen, and king of Dublin and Deira, is to be clearly distinguished from his kinsman and contemporary, Olaf Sitricson [q. v.] He was the great-grandson of Ivar Beinlaus, son of Regnar Lodbrok, and therefore of the famous race of the Hy Ivar. His father was the Godfrey, king of Dublin, brother or cousin of Sitric, king of Deira, who vainly attempted to wrest Deira from Æthelstan [q. v.] in 927. The earliest trustworthy mention of Olaf Godfreyson is in 933, when, in alliance with the Danes of Strangford Lough, he plundered Armagh. In the same year he allied himself with the lord of Ulster in the plunder of what is now Monaghan, but was overtaken and defeated by Muircheartach (d. 943) [q. v.], king of Ailech (Ann. Ultonienses, ap. O'Conor, Rer, Hibern. Scriptt. iv. 260; Annals of the Four Masters, ed. O'Donovan, ii. 629). In 934 he succeeded his father in the Norse kingdom of Dublin (Ann. Ult. iv. 261, and Four Masters, ii. 631, where the dates given are two years behind the correct date). Next year he was again in the field, and took Lodore, near Dunshaughlin, in what is now Meath. In 936 or 937 he plundered the abbey of Clonmacnoise in Offaly, and billeted his soldiers for two nights on the monks (ib.) Possibly taking advantage of Olaf's absence, Donnchadh, king of Ireland, burnt Dublin. The former, however, was not long delayed by the ruin of his capital, for on 1 Aug. 937 he led an expedition against certain Danes who were sojourning on Lough Rea. These he made prisoners and brought to Dublin, whence the inference (Todd, War of the Gaedhil with the Gaill, p. 281, Rolls Ser.) that the object of this attack was to compel the Danes to take part in the ensuing expedition to England (Four Masters, ii. 633, and Annals of Clonmacnoise, quoted by O'Donovan, ib.; cf. also Ann. Ult. iv. 261). In 937 Olaf fought at the great battle of Brunanburh under the leadership of Olaf Sitricson [q. v.] In the rout of the northern forces he escaped to his ships, and returned to Dublin in 938 (Anglo-Saxon Chron. ii. 88, Rolls Ser.; Ann. Ult. iv. 263; Four Masters, ii. 635). The plunder of Kilcullen in Kildare may more probably be ascribed to Olaf Sitricson, and to a later date; but the year of Olaf Godfreyson's return was again marked by the burning of Dublin and the plunder of the Norse territory by King Donnchadh (ib.) Shortly afterwards (in 939) Olaf apparently left Dublin, and, soon after Æthelstan's death in 940, accepted, jointly with Olaf Sitricson, a vaguely recorded invitation from the Northumbrians to 'Olaf of Ireland' to be their king (A.-S. Chron. ii. 89; Flor. Wig. i. 133, Engl. Hist. Soc.; Will. Malm. i. 157, Rolls Ser.; Rog. Hov. i. 55, Rolls Ser.) With his kinsman he probably shared the kingship until his death in an obscure fight at Tynningham, near Dunbar, in 941 (A.-S. Chron. ii. 89; Sym. Dunelm. Hist. Reg. ii. 94, Rolls Ser.; Rog. Hov. i. 55; Hen. Hunt. p. 162, Rolls Ser.)
Olaf married Alditha, daughter of a certain jarl named Orm (Matt. Westmon. ap. Luard, Flores Historiarum, i. 498, Rolls Ser.)
[In addition to the authorities cited in the text, see Ware's Antiq. Hibern. p. 131; Hodgson's Northumberland, ed. Hinde, i. 148 seq.; Robertson's Early Kings of Scotland, i. 63; Skene's Celtic Scotland, i. 361.]