Montacute Castle was besieged by English rebels from Somerset, Dorset and neighbouring areas in 1069 and its relief required the assembly of a considerable force, drawn chiefly from the Norman garrisons of London, Winchester and Salisbury. This army was led by the Norman bishop, Geoffrey of Coutances, whose large landholdings were also threatened. The rebels were taken by surprise and bloodily defeated, putting an end to the revolt. Joseph Bettey has suggested that "the devastation in the surrounding area which followed the English defeat may explain why so many manors in south Somerset are recorded in the Domesday Survey as having decreased in value". The English dead were buried in a mass grave to the west of the village in a sloping field now known as "Under Warren". Village tradition has it that two hilltop fortifications were built: first a wooden clamshell fort with motte & bailey, later replaced by a stone castle. However little evidence to prove the existence of the stone structure exists, except a note in the parish records that two loads of stone were taken from the site by the neighbouring parish of Martock. A church or chapel dedicated to St Michael later replaced the castle. Excavations of the hilltop have been limited and inconclusive.
