Uncertainties over the succession probably contributed to much of the unrest in the reigns of Malcolm IV and William I. Malcolm's reign began with a prolonged rising in the west in November 1153 - led by the immensely powerful 'Lord' or rí of Argyll, Somerled - which was connected with the claims of Malcolm macHeth, who had married a sister of Somerled and may have traced descent from Alexander I. David I had faced a northern revolt in 1130; Malcolm IV was threatened with the prospect of a combined rising of the north and west. The reign ended shortly after another rising by Somerled, who brought a fleet up the Clyde as far as Renfrew in 1164. In the meantime, Malcolm had been forced to cede Cumberland and Westmorland to Henry II of England (1154-89) in 1157 and this may have increased his difficulties in nearby Galloway, which would be a thorn in the side of macMalcolm kings until the 1230s. In 1160, shortly after he returned from a military campaign in Aquitaine, where he had been called by his liege lord Henry II, Malcolm was confronted with what would appear to have been an orchestrated protest rather than a revolt by six of his earls, who besieged him in his own Castle of Perth. The attempted coup - if such it was - was resisted by Malcolm, who embarked on three successive punitive expeditions into Galloway.

This episode and the reign itself have been called a 'crucial turning-point' in the history of both the macMalcolm dynasty and the Norman settlement.45 Yet the episode is obscure and the identity of only one of the six earls - Ferteth ofStratheam - is known. By 1164, it is true, Somerled had been killed and the first episode in the long subjugation of Galloway completed with the deposing of Fergus, the so-called 'King of Galloway', who ended his days as a canon in the Augustinian house at Holyrood. Marriage alliances involving two of Malcolm's sisters had been concluded in 1161 and 1162 with Brittany and Holland. Yet each rebellion during the reign seems to have been linked to an uncertain succession.46 In terms of royal authority, Galloway, although temporarily subdued during the reign, had been added to Moray as another dark comer of the land. The legacy left by Malcom IV to his brother William was a distinctly mixed one.