King Sweyn Forkbeard was a Viking king who ruled over Denmark and later became the King of England. He was born around 960 AD and is known for his military campaigns against England, particularly during the reign of King Æthelred the Unready. Sweyn successfully invaded England in 1013, leading to his brief claim to the English throne. Sweyn Forkbeard was the father of King Cnut, who would later consolidate power in both England and Denmark. Sweyn's reign marked a significant period in Viking history, as it contributed to the eventual establishment of Viking rule in England and the blending of cultures between the Norse and the Anglo-Saxons.