The House of Wessex, also known as the House of Cerdic, the House of the West Saxons, the House of the Gewisse, the Cerdicings and the West Saxon dynasty, refers to the family, traditionally founded by Cerdic of the Gewisse, that ruled Wessex in Southern England from the early 6th century. The house became dominant in southern England after the accession of King Ecgberht in 802. Alfred the Great saved England from Viking conquest in the late ninth century and his grandson Æthelstan became first king of England in 927. The disastrous reign of Æthelred the Unready ended in Danish conquest in 1014. Æthelred and his son Edmund Ironside attempted to resist the Vikings in 1016, but after their deaths the Danish Cnut the Great and his sons ruled until 1042. The House of Wessex then briefly regained power under Æthelred's son Edward the Confessor, but lost it after the Confessor's reign, with the Norman Conquest in 1066. All kings of England since William II have been descended from the House of Wessex through William the Conqueror's wife Matilda of Flanders, who was a descendant of Alfred the Great through his daughter Ælfthryth. Additionally, kings since Henry II have been descended from English kings from the House of Wessex through Henry I's wife Matilda of Scotland, who was a great-granddaughter of Edmund Ironside.