Athelney is a village in Somerset, England. It was formerly an isolated island in the very swampy and impassable marshlands of the Somerset Levels, and the King of Wessex Alfred the Great used the swamplands as his hideout after the Vikings under Guthrum drove him out of Winchester. He and his loyal followers waged guerrilla war from the Somerset marshlands until they scored a decisive victory at the Battle of Edington, after which Alfred built an abbey at Athelney. In 1539, it was destroyed during King Henry VIII's Dissolution of the Monasteries, and its rubble was sold. Today, it is a village in the Sedgmoor district of Somerset.