The Kingdom of Sussex had its initial focus in a territory based on the former kingdom and Romano-British civitas of the Regni and its boundaries coincided in general with those of the later county of Sussex. For a brief period in the 7th century, the Kingdom of Sussex controlled the Isle of Wight and the territory of the Meonwara in the Meon Valley in east Hampshire. From the late 8th century, Sussex seems to have absorbed the Kingdom of the Haestingas, after the region was conquered by the Mercian king Offa.
The Kingdom of Sussex had its initial focus in a territory based on the former kingdom and Romano-British civitas of the Regni and its boundaries coincided in general with those of the later county of Sussex. For a brief period in the 7th century, the Kingdom of Sussex controlled the Isle of Wight and the territory of the Meonwara in the Meon Valley in east Hampshire From the late 8th century, Sussex seems to have absorbed the Kingdom of the Haestingas, after the region was conquered by the Mercian king Offa.