Alexander II (Mediaeval Gaelic: Alaxandair mac Uilliam; Modern Gaelic: Alasdair mac Uilleim) (24 August 1198 – 6 July 1249), King of Scots, was the only son of William the Lion and Ermengarde of Beaumont. He was born at Haddington, East Lothian, in 1198, and spent time in England (John of England knighted him at Clerkenwell Priory in 1213) before succeeding to the kingdom on the death of his father on 4 December 1214, being crowned at Scone on 6 December the same year.
In the same year Alexander joined the English barons in their struggle against John I of England, and led an army into the Kingdom of England in support of their cause. The Scottish Army of Alexander II reached the south coast of England at the port of Dover awaiting the arrival of the French Army under the Dauphin. But King John died and the Pope and the English aristocracy changed their attitude, which meant the French army has returned home shortly after taking London and the Scottish army returned to Scotland. Peace between John's youthful son Henry III of England and the French prince Louis VIII of France and Alexander followed.
Diplomacy further strengthened the reconciliation by the marriage of Alexander to Henry's sister Joan of England on 18 June or 25 June 1221.
The next year marked the subjection of the hitherto semi-independent district of Argyll. Royal forces crushed a revolt in Galloway in 1235 without difficulty; nor did an invasion attempted soon afterwards by its exiled leaders meet with success. Soon afterwards a claim for homage from Henry of England drew forth from Alexander a counter-claim to the northern English counties. The two kingdoms, however, settled this dispute by a compromise in 1237. This was the Treaty of York which defined the boundary between the two kingdoms as running between the Solway Firth (in the west) and the mouth of the River Tweed (in the east).
Joan died in March, 1238 in Essex, and in the following year, 1239, Alexander remarried. His second wife was Marie de Coucy. The marriage took place on 15 May 1239, and produced one son, the future Alexander III, born in 1241.
A threat of invasion by Henry in 1243 for a time interrupted the friendly relations between the two countries; but the prompt action of Alexander in anticipating his attack, and the disinclination of the English barons for war, compelled him to make peace next year at Newcastle. Alexander now turned his attention to securing the Western Isles, which still owed a nominal allegiance to Norway. He successively attempted negotiations and purchase, but without success. Alexander next attempted to persuade Ewen, the son of Duncan, Lord of Argyll, to sever his allegiance to Haakon IV of Norway. Ewen rejected these attempts, and Alexander sailed forth to compel him.
But on the way he suffered a fever at the Isle of Kerrera in the Inner Hebrides, and died there in 1249. He was buried at Melrose Abbey, Roxburghshire. His son Alexander III succeeded him as King of Scots.