In the west, the spearhead of kings of Scots since at least the 1140s had been another Norman family, the Stewarts. Although 'official' chronicles portray the actions of Somerled, Lord of the Isles, in 1164 as those of a rebel against his sovereign, he would have seen himself as a victim of Stewart aggression. It was not until after 1244, when relations with England were again in a settled state, that Alexander II turned seriously to his western frontier. He first used the tactics of trying to buy out the interest of King Hakon IV of Norway, who enjoyed suzerainty over both Man and the Western Isles. When diplomacy and bribery failed, force took their place. In 1249, the year of his death, Alexander II assembled a fleet and army to penetrate the Firth of Lorn and northern Argyll. He died on the Isle of Kerrera, across the bay from present-day Oban, with Argyll but not the Isles under a royal control. The foundation for further expansion westward was laid, but it took place only after his son, Alexander III, came of age in 1260. It was then that the Stewarts (who had gained the earldom of Menteith by marriage in 1261 on the death of Earl Walter) were again on the move, pushing the effective frontier of the kingdom out from the Ayrshire coastline across the Firth of Clyde into Kintyre and Knapdale.

The new eight-year-old king, Alexander III (1249-86), the first boy to succeed for almost a century, was quickly put through a rite of inauguration, which combined tradition - being held in the open air and involving the solemn recitation in Gaelic of the new king's long genealogy back to the eponymous Scota, daughter of Pharaoh - and hints of a new-style coronation.54 Minors had succeeded in recent times, in 1153 and 1214, but neither had involved a minority that would last ten years. For many historians, the 1250s saw the first of many minorities which would mark the next 300 years of Scottish history as essentially being a struggle between overmighty nobles and the crown. The faction-fighting of the 1250s also had, in some interpretations, the added ingredient of English interference, which split the nobles into 'native' and 'pro-English' factions. Most views of a reign which lasted for thirty-six years - the second longest of the twelfth and thirteenth centuries - have either dwelt on the minority with which it began or been conditioned by the crisis of the 1290s which followed. The familiar story of a king unleashed after a strife-torn minority has in much historical writing become the standard plot of later reigns, including almost all the Stewart kings from James I onwards. The status of both Alexander III and his kingdom has, however, also had to bear the weight of a 'golden age', which was brought to a close by the prolonged crisis inflicted upon Scotland by the Wars of Independence.