Coordinates: 50°43′54″N 0°47′21″W / 50.731566°N 0.789127°W
Cymenshore (also : Cymensora,Cumeneshore, Cumenshore, Cimeneres horan, Cymeneres horan.) is a place in Southern England where, according to the Anglo-Saxon Chronicle, Ælle of Sussex landed in AD 477 and battled the Britons with his three sons Cymen, Wlencing and Cissa, after the first of whom Cymenshore was held to have been named. Its location is unclear but was probably near Selsey.
The account of Ælle and his three sons landing at Cymenshore appears in the Anglo-Saxon Chronicle, a collection of seven vernacular manuscripts, commissioned in the 9th century, some 400 years or more after the events at Cymenshore. The legendary foundation of Saxon Sussex, by Ælle, is likely to have originated in an oral tradition before being recorded in the Anglo-Saxon Chronicle. From 491 until the arrival of Christianity in the 7th century, there was a dearth of contemporary written material. Information about early Sussex derived from the chronicle has been modified by our knowledge of what was happening elsewhere in England and by a growing body of archaeological evidence.
The Chronicle goes on to describe a battle with the British in 485 near the bank of Mercredesburne, and a siege of Pevensey in 491 after which the inhabitants were massacred.