This conclusion is, that what may be termed the shares of the respective lines of Paul and Erlend, the sons of Earl Thorfinn and others, in the Caithness earldom lands probably went respectively between 1231 and 1239 and afterwards in the following manner.
The right to succeed to the share of Paul passed, on his descendant Earl John's death in 1231, to Earl John's only child then alive, the nameless hostage daughter, who, according to our theory, had after 1st August 1214 married Magnus, son of Earl Gilchrist of Angus by his second marriage with either Ingibiorg or Elin, both sisters of Harald Ungi, and both older than Ragnhild. But the title of Earl of Caithness and the enjoyment of the whole earldom was on Earl John's death temporarily conferred, in addition to his title of Earl of Angus, on Malcolm, Earl of Angus, and nephew of Magnus the husband of John's hostage daughter, as being the head of the Angus family and one of the most powerful earls in Scotland, pending a general settlement of the affairs of Sutherland and Caithness; and Malcolm held his own Earldom of Angus, and, in addition, for the Crown, as _Custos_, trustee, or administrator _pendente lite_, held Caithness after 22nd April 1231 and certainly at 7th October 1232, possibly till 3rd July 1236, when the following settlement was made.
Caithness, without Sutherland, was with the title of Earl of Caithness, North and South, confirmed to Earl Magnus II by two grants, the one of North Caithness in right of his wife and the other of South Caithness in right of his mother. The estate of Sutherland was after 10th October 1237 erected into an earldom in the person of William, who was the eldest son of Hugo Freskyn, and was then owner of the estate, this earldom being, as stated in the Diploma of the Orkney Earls, "taken away from Magnus II" in his lifetime, possibly out of South Caithness, by Alexander II.
On Magnus' death in 1239, Gillebryd or Gillebride, called in the Icelandic Annals Gibbon, who was either a son or younger brother of Magnus, succeeded Magnus II in the Orkney and Caithness titles and in the Paul share of the Caithness earldom, and it appears from a grant of the advowson of Cortachy on 12th December 1257 that Matilda daughter of Gillebert, "then late Earl of Orkney," married Malise Earl of Stratherne. On Gillebride's death in 1256, his son Magnus III succeeded to Orkney and to the share of Paul in the Caithness earldom, as held by Earl Magnus II and Earl Gillebride his successor, that is without the Sutherland earldom, and without Freskin and Johanna's share of Caithness.