King Cnut ruled England from 1017 to 1035 and left behind him a legacy of peace, law and order. However, the beginnings of his kingship were less auspicious. He was a cruel and vicious warrior, who invaded England with his father Swegen Forkbeard, perhaps at a tender age. After Swegen's death in 1014 Cnut went home to Denmark to gather his forces. He returned the following year and conquered much of England in his bid for the Crown, but even on the death of Aethelred II the English refused to proclaim him king. However, his victory over the alternative candidate, Aethelred's son King Edmund Ironside, at the battle of Ashingdon, forced a division of the country between the two. Shortly afterwards, Edmund died and Cnut became undisputed ruler. M K Lawson brings to life the reality of this paradoxical king: his ruthlessness in the face of his enemies alongside his piety and law-giving nature. He also provides an insight into how a Danish king managed to accommodate himself to an English system of law and order that has resonated through history.