The Haestingas, or alternatively Heastingas or Hæstingas, were one of the tribes of Anglo-Saxon Britain. Not very much is known about them. They settled in what became east Sussex sometime before the end of the 8th century. A 12th-century source suggested that they were conquered by Offa of Mercia in 771. They were also recorded in the Anglo-Saxon Chronicle (ASC) as being an autonomous grouping as late as the 11th century.
The foundation legend of the Kingdom of the South Saxons is given by the Anglo-Saxon Chronicle, which states that in the year AD 477 Ælle arrived at a place called Cymenshore in three ships with his three sons. Traditionally Cymenshore is thought to have been located around the Selsey area, in the south west of Sussex. However the archaeological evidence indicates that the principal area of settlement in the 5th century, for the South Saxons, has been identified as between the lower Ouse and Cuckmere rivers in East Sussex, based on the number of Anglo-Saxon cemeteries there.