Harold I (died 17 March 1040), commonly known as Harold Harefoot, was King of England from 1037 to 1040. His nickname "Harefoot" is first recorded as "Harefoh" or "Harefah" in the twelfth century in the history of Ely Abbey, and according to some late medieval chroniclers it meant that he was "fleet of foot".
The son of Cnut the Great and Ælfgifu of Northampton, Harold was elected regent of England following the death of his father in 1035. He initially ruled England in place of his brother Harthacnut, who was stuck in Denmark because of a rebellion in Norway that had ousted their brother Svein. Although Harold had wished to be crowned king since 1035, Æthelnoth, Archbishop of Canterbury, refused to do so. It was not until 1037 that Harold, supported by earl Leofric and many others, was officially proclaimed king. The same year, Harold's two step-brothers Edward and Alfred returned to England with a considerable military force. Alfred was captured by Earl Godwin, who had him seized and delivered to an escort of men loyal to Harefoot. While en route to Ely, he was blinded and soon after died of his wounds.