When King Edgar died, he bequeathed Scotland north of the Forth to his brother Alexander, but gave the sovereignty of Lothian and Cumbria to their younger brother David.
Born around 1077, Alexander was the fifth son of Malcolm III and St Margaret. Named after Pope Alexander II, he was described by one chronicler as 'a lettered and godly man', but he was also known as 'Alexander the Fierce' after dealing ruthlessly with an uprising in Moray.
In 1114 he served as leader of a contingent in Henry I of England's campaign against the Welsh (he was technically a vassal of the English king).
Alexander married Henry's illegitimate daughter Sybilla (Henry had married Alexander's sister Maud). Sybilla died suddenly in 1122, leaving no children.
Alexander died at Stirling on 23 April 1124.
Image: The Queen visits Stirling Castle, where in 1110 Alexander I invested a chapel.