Who prepared for an invasion by a king who had Earl Skule Bårdsson as a rival?
Findlater Castle:  King Alexander III of Scotland repaired this castle in the 1260s in preparation for an invasion by King Haakon IV of Norway. Haakon IV of Norway: Haakon Haakonsson (c. March/April 1204 – 16 December 1263) (Old Norse: "Hákon Hákonarson"; Norwegian: "Håkon Håkonsson"), sometimes called Haakon the Old in contrast to his son with the same name, and known in modern regnal lists as Haakon IV, was the King of Norway from 1217 to 1263.
i don't know