The famous image of a king ordering the tide to stop is usually told as the ultimate story of arrogance, but the 12th-century chronicler Henry of Huntingdon recorded it to make the opposite point: a ruler deliberately getting his feet wet to show his flattering courtiers that earthly power has hard limits. This deep dive uncovers the real man behind that misunderstood beach legend.

We trace Cnut from an obscure Viking prince, born around 995, into the ruler of a vast multinational North Sea empire. Along the way we examine the mutilation of hostages at Sandwich, an invasion financed on the promise of England's tax revenue, victory at the Battle of Assandun, the enormous Danegeld payment, his marriage to Emma of Normandy, and the addition of Denmark and Norway before his sudden death in 1035.

• How Henry of Huntingdon's tide story w ...