was the son of Malcolm II's eldest daughter Bethoc and her husband Crinan,
Lay Abbot of Dunkeld. He was about 33 when he succeeded his grandfather.
Married to a cousin of Siward, Earl of Northumberland, he may have favoured
southern ways and this is perhaps why he became unpopular with his subjects.
He was not the best tactician and in 1038 he marched south to besiege Durham
but he was beaten off, with heavy losses.
Duncan attempted to impose his over lordship over Moray (an
independent dynasty) by military force. He was then twice defeated by the
Earl of Orkney's son, Thorfinn, before being killed in battle by Macbeth,
one of his commanders, near
Morayshire on 14 August 1040 and is at rest with other Scottish in