Dunster Castle evidence of a fortification at Dunster was an Anglo-Saxon "burgh". This was built on the summit of the hill and was possibly intended to protect the region against sea-borne raiders; by the mid-11th century it was controlled by a local nobleman called Aelfric. In 1066 the Normans invaded south-east England, defeating the English forces at the battle of Hastings: in the aftermath of the victory, William the Conqueror entrusted the conquest of the south-west of England to his half-brother Robert of Mortain. Expecting stiff resistance, Robert marched west into Somerset, supported by forces under Walter of Douai, who entered from
Dunster Avill, offering a natural defence and making the village an inland port. Nearby is the Dunster Park and Heathlands Site of Special Scientific Interest noted for nationally important lowland dry heath, dry lowland acid grassland, wood-pasture with veteran trees and ancient semi-natural oak woodland habitats. The fauna of the lowland heath includes the heath fritillary ("Mellicta athalia"), a nationally rare butterfly. The assemblage of beetles associated with the veteran trees is of national significance because of the variety and abundance of species. Along with the rest of South West England, Dunster has a temperate climate which is generally wetter and