The county of Suffolk ("Sudfole", "Suthfolc", meaning 'southern folk') was formed from the south part of the kingdom of East Anglia which had been settled by the Angles in the latter half of the 5th century. The most important Anglo-Saxon settlements appear to have been made at Sudbury and Ipswich. Before the end of the Norman dynasty, strongholds had arisen at Eye, Clare, Walton and Framlingham. Probably the establishment of Suffolk as a separate shire was scarcely completed before the Conquest, and although it was reckoned as distinct from Norfolk in the Domesday Survey of 1086, the fiscal administration of Norfolk and Suffolk remained under a single sheriff until 1575. The boundary of the county has undergone very little change, though its area has been considerably affected by coast erosion. Parts of Gorleston and Thetford, which formerly belonged to the ancient county of Suffolk, are now within the administrative county of Norfolk, and other slight alterations of the administrative boundary have been made. Under the Local Government Act of 1888 Suffolk was divided into the two administrative counties of East and West Suffolk.