Ogmund was born in 1043, and was the only son of Sigurd of Cronk and his wife Helga. Once Sigurd had returned from Iceland with young Godred Crovan and his mother Gerda, the two lads were brought up together first as foster brothers, and later as step brothers when on Helga's death Sigurd married Gerda. The couple had a son, Sigmund. The three boys became close friends.
Sigurd was the leading man in Sodor at the time and on his death in 1063 Ogmund succeeded to that position. By that time Thorfinn the Mighty's power was waning and just as Sigurd had trained him to do Godred set about regaining his father‘s former kingdom, leaving Ogmund as his trusted Lieutenant (or Jarl) in Sodor.
It was in this capacity that Ogmund welcomed Thorkell of Norwich and his men in 1067, and settled them in Kellsthorpe, Ulfstead and elsewhere, and with their aid he squeezed the last of Fingall’s, Thorfinn's puppet King, soldiers from the Island. His daughter, Gyda, married Thorkell in 1068.
With Sodor secure Godred could continue his conquest of the Isles, Dublin, and finally Man at the Battle of Skyhill in 1079. To Godred’s lasting grief Ogmund fell in the battle, and the Ogmund Saga was first sung in its entirety at his funeral wake. It not only describes the hero’s life and deeds, but traces his warrior lineage through those of his father Sigurd, to those of his namesake grandfather Ogmund, a battle-comrade of King Godred MacHarold. He was succeeded as Viceroy by his half brother, Sigmund.
The original Saga ends with Ogmund’s death; but there is a continuation of later date which implies later events such as the defeat of the Normans (1089 and 1094) and Sigmund’s accession to the throne of an independent Sodor. The Saga provides a valuable check on Irish and Manx accounts of the period and where they differ Sudrians have no hesitation in following the Ogmund Saga. Written in old Norse, parts of it are now illegible. It was found by Albert Regaby, Lord Harwick, at Peel Godred and is now held at the Island Records Office at Suddery.