St Michael’s Mount at Montacute is the site of a Norman motte and bailey castle built on a natural conical hill overlooking the low‑lying ground to the north and east. Motte and bailey castles were introduced into Britain by the Normans and consisted of a steep mound, the motte, crowned by a timber or stone tower, with an adjoining embanked enclosure, the bailey, containing additional buildings. These castles served as garrison forts, strongholds, administrative centres and aristocratic residences. Their strategic siting made them among the most visually dominant monuments of the early post‑Conquest landscape. More than six hundred examples are known nationally. Montacute is one of only two castles in Somerset recorded in the Domesday Book.
The hill at Montacute was scarped to form the motte, with an outer terrace around three sides and a bailey on the south‑east slope. The summit of the motte is oval, measuring about 50 metres by 30 metres. Around the south‑eastern sides, seven metres below the top, runs an upper terrace about 20 metres wide, with an outer face up to seven metres high. Below this lies the bailey, extending to the foot of the hill. The bailey is lobe‑shaped and encloses about 0.4 hectares. Its ditches cut into the edge of the upper terrace and diverge down the hill to the east and south‑east, becoming a scarp around the lower end. The ditches average four metres deep and ten metres wide. The scarp reaches nine metres in height, with a shallow ditch at its base. A broad bank about one metre high encloses the bailey on the south‑west, south and north sides.
The interior of the bailey is terraced to create usable platforms. Two broad steps, each about 25 metres wide, lie at the top and bottom, with two narrower steps nine metres wide between them. The outer terrace around the other sides of the hill lies about fifteen metres below the summit and is about 35 metres wide. Below it is a fifteen‑metre scarp to the base of the hill, with a shallow ditch running around it. On the north‑west side a bank two metres high separates the outer terrace from the base of the motte, forming an inner ditch created by steepening the motte. This ditch runs around to meet the ends of the upper terrace.
The approach from the foot of the hill to the outer terrace is by a hollowed trackway on the north‑west. The ascent from the upper terrace to the summit is by a path from the south‑west side just inside the bailey. The approach from the outer terrace to the upper terrace is more complex. The upper terrace extends beyond the bailey ditches to form platforms below the motte on the north‑east and south‑west. Terraced tracks lead up to these from the outer terrace, running outside the bank and ditch. The ditch turns outward to cut across these tracks where they meet the platforms. These appear to have been the original entrances to the castle and may have supported entranceworks or barbicans. The relationship between the terraces, banks and ditches suggests more than one phase of construction.
At the bottom of the bailey on the south‑east is a broad stepped hollow, probably a later quarry. The hill was known in Saxon times as Lodegaresbergh, and documentary references suggest an earlier Saxon stronghold here, though this has not been confirmed archaeologically. A manuscript of Waltham Abbey recounts the discovery of a Saxon holy cross on the hill. The Norman castle, built by Robert of Mortain during the Conquest, may have been deliberately placed on this sacred site. The castle was besieged in a revolt in 1068. By 1102 it had passed out of use and the hill, now known by the Norman name Mons Acutus, was granted to the newly founded priory in the village.
Leland, writing in the sixteenth century, recorded that the castle had partly fallen into ruin and had partly been dismantled to enlarge the priory. He noted that no building remained except a chapel set over the dungeon. This chapel, dedicated to St Michael, is first recorded in 1102 and was said by Camden to have been built after the castle was demolished. References such as these suggest that the castle was built of stone. In 1246 the king granted the priory a three‑day annual fair at the chapel of St Michael of Montacute. The broad terrace on the north‑west of the hill would have provided a suitable site for such a fair.
The priory was dissolved in 1539 and the fair appears to have lapsed at the same time. In 1518–19 the churchwardens of Tintinhull paid for two loads of stone from the castle, though this may have come from the quarry at the foot of the bailey. The chapel was last recorded in 1630. The present folly tower on the summit was erected in 1760 as a landscape feature. It is cylindrical with a truncated conical top, three metres in diameter and twelve metres tall, with an internal staircase leading to an external stair at the top. Earlier foundations are visible inside and around its base.
A small excavation on the summit in 1989 found evidence of a building thought to be the medieval chapel, along with a layer of rubble containing early medieval pottery, possibly from the demolition of the castle. The folly tower is excluded from the scheduling, though the ground on which it stands is included.
