Alexander I of Scotland or Alaxandair mac Maíl Coluim was the fourth son of Máel Coluim mac Donnchada by his wife Margaret, grand-niece of Edward the Confessor. He was named in honour of Pope Alexander II.
Alexander was his unmarried brother Edgar’s heir, perhaps throughout his reign. On the death of Edgar in 1107 he succeeded to the Scottish crown. Edgar’s will granted David the lands of the former kingdom of Strathclyde or Cumbria, and this was apparently agreed in advance by Edgar, Alexander, David and their brother-in-law Henry I of England. However, in 1113, perhaps at Henry’s instigation, and with the support of his Anglo-Norman, David demanded, and received, additional lands in Lothian along the Upper Tweed and Teviot. David did not receive the title of king, but of “prince of the Cumbrians”, and his lands remained under Alexander’s final authority.
Alexander’s marriage with Henry’s illegitimate daughter Sybilla de Normandy may have occurred as early as 1107, or as at late as 1114. Sybilla died in unrecorded circumstances at Eilean nam Ban (Kenmore on Loch Tay) in July, 1122 and was buried at Dunfermline Abbey. Alexander did not remarry.
Alexander had at least one illegitimate child, Máel Coluim mac Alasdair, who was later to be involved in a revolt against David I in the 1130s. He was imprisoned at Roxburgh for many years afterwards, perhaps until his death some time after 1157.
For all his religiosity, Alexander was not remembered as a man of peace. He manifested the terrible aspect of his character in his reprisals in the Mormaerdom of Moray. Alexander was holding court at Invergowrie (by Dundee) when he was attacked by “men of the Isles”. Alexander pursued them north, to “Stockford” in Ross (near Beauly) where he defeated them. This was why he was named the “Fierce”. The Mormaerdom or Kingdom of Moray was ruled by the family of Mac Bethad mac Findláich and Lulach mac Gille Coemgáin; not overmighty subjects, but a family who had ruled Alba within little more than a lifetime. Who the Mormaer or King was at this time is not known, it may have been Óengus of Moray or his father, whose name is not known. As for the Mearns, the only known Mormaer of Mearns, Máel Petair, had murdered Alexander’s half-brother Donnchad mac Maíl Coluim in 1094.
Alexander died in April 1124 at his court at Stirling; his brother David, probably the acknowledged heir since the death of Sybilla, succeeded him.