The Battle of Sandwich in 851 was the first known naval battle in English history. It was a Kentish victory against a Danish Viking fleet.
In 851 King ÃÂthelwulf of Wessex scored a major victory at the battle of Aclea over an army drawn from 350 Danish ships. He had appointed his eldest son ÃÂthelstan under-king of Kent, and in the same year ÃÂthelstan and his ealdorman Ealhhere defeated a Danish fleet off Sandwich in Kent.
The Anglo-Saxon Chronicle recorded under 851 that: "King ÃÂthelstan and Ealdorman Ealhhere fought in ships, and slew a great army at Sandwich in Kent, and captured nine ships, and put the others to flight.