Administrative county (pop., 2001: 753,612), southeastern England.
It borders the English Channel , and its administrative centre is Chichester . There is evidence of settlements dating from prehistoric times in the region. A dynasty of British chieftains was in the area just before the Roman invasion. After the Romans left, Saxon invaders conquered Sussex in the late 5th century. They were overcome by the peoples of neighbouring Wessex and later by the Normans, who built castles and monasteries. Since the beginning of the 14th century, the growth of seaside resorts has been important in the development of the area's coast; inland, much of it remains rural.