Anglo-Saxon England was early medieval England, existing from the 5th to the 11th century from the end of Roman Britain until the Norman conquest in 1066. It consisted of various Anglo-Saxon kingdoms until 927 when it was united as the Kingdom of England by King Æthelstan (r. 927 - 939). It became part of the North Sea Empire of Cnut the Great, a personal union between England, Denmark and Norway in the 11the century.