The inner court of Thornbury Castle is listed at Grade I for the following principal reasons:
* Architectural interest: Thornbury Castle is recognised as being one of the finest examples of Tudor domestic architecture in the country, taking inspiration from royal buildings both lost and extant;
* Historic interest: the castle was developed from 1511 for Edward Stafford, 2nd Duke of Buckingham, and remained unfinished at his execution for treason in 1521; the castle represents the height of architectural taste and craftsmanship, and illustrates the Duke's ambition, which ultimately led to his downfall;
* Rarity and intactness: despite neglect, and extensive restoration, the building stands as a remarkably intact example of high status domestic architecture of the period;
* External and internal features: external and interior C16 features of outstanding interest, including the compass windows on the south front, the elaborate chimney stacks, and original stone fireplaces within the south range;
* Historical development: Anthony Salvin's restoration and his re-ordering of the south range interior, is of interest as an informed C19 interpretation of a Tudor building;
* Group value: the inner court buildings have strong group value as part of the Thornbury Castle site, which includes the Grade I-listed outer court and garden walls, the two Grade II-listed lodges, the Grade II Registered Park and Garden, the scheduled remains of the medieval manor house and C16 privy garden; the Church of St Mary the Virgin, listed at Grade I, stands immediately adjacent to the site.
In 1066 it was recorded that the manor of Thornbury was held by Beorhtric, son of Aelfgar, although by Domesday it was in the hands of King William. The manor has changed hands many times during its history, being held by the Crown at intervals. In the C12 and C13, it was part of the earldom of Gloucester; the de Clare family was responsible for the foundation of the borough of Thornbury in 1243, to the south of the church and manor house. A major fire in 1236 destroyed the manor house, following which Henry III ordered that the Constable of St Briavels supply 20 oak trees from the Forest of Dean for its rebuilding. The house came to Hugh Audley on his marriage to Margaret de Clare in 1317, passing to Audley’s son-in-law, Ralph Stafford, in 1347. It is understood that a licence to crenellate was granted in the C14, and early-C14 and C15 financial accounts provide evidence for an extensive complex in which an inner court, entered through a central gate, gave access to a hall, orientated north to south, with kitchen offices to the west and a chapel, begun in 1340 and completed in 1435, to the east of the hall. Accounts also record an outer courtyard containing a range of service buildings.
The manor house was forfeited at the execution for treason of Henry Stafford, 2nd Duke of Buckingham, following the Rebellion of 1483, but was restored to the family and inherited by his son Edward, 3rd Duke, in 1498, who made it his principal seat. Plans were laid for the creation of an ambitious and outwardly fortified house and a licence to fortify, crenellate, and embattle the manor house was granted in 1510. With the hall and chapel of the existing manor house forming the east range of an inner courtyard, Buckingham set about building an elaborate palace-castle, which demonstrated the involvement of masons of the highest quality, and was apparently inspired by Richmond Palace, at that time England’s most splendid royal residence. To complement his bold plans for the castle, Buckingham enclosed 1500 acres of parkland between 1510 and 1517.
Edward, Duke of Buckingham, was executed on the orders of Henry VIII following an investigation for treason in 1521 – the Duke's ostentatious behaviour and wealth, as evidenced by his lavish building programme, having exacerbated the suspicion with which he was viewed – and the estate was confiscated, remaining in Crown ownership until 1554. Henry sent surveyors to make a record of his new acquisition shortly after Buckingham’s death, and their account provides a detailed description of the castle and estate. Although works were not recommenced, the buildings were maintained and periodically used; Princess Mary visited during the 1520s, and Henry VIII and Anne Boleyn stopped on a royal progress in 1535. Thornbury Castle was restored to the Staffords in 1554 when it was granted to Buckingham’s son, Lord Henry Stafford, by Queen Mary. The upkeep of the castle proved too expensive, however, and it fell into ruin, eventually coming into the ownership of a branch of the Howard family in 1637 and remaining in their hands until the 1960s.
The east range, comprising the original medieval hall and chapel, was demolished at some point before 1732. No pictorial representations survive of the range, which is described in a detailed estate inventory made in the late C16; archaeological investigation has demonstrated the survival of this part of the castle as a buried feature. Although part of the castle – principally the section of the west range to the south of the gatehouse – served as lodgings and a farmhouse in the C18 and early C19, much of the building was ruinous, and it was not until the C19 that it was brought back into use as a high-status residence. In 1803 the local architect Francis Greenway exhibited designs for 'Thornbury Castle restored […]', and he may have been commissioned to work on the castle in 1809-11. In 1849 Henry Howard commissioned Anthony Salvin to restore the castle for his private accommodation. The castle is now (2013) a hotel and restaurant.
A great house, the principal part of which was built between circa 1511 and 1521 for Edward, 3rd Duke of Buckingham, with extensive C19 restoration and alteration by Anthony Salvin, and alterations made as a result of the building's conversion to an hotel, including an addition of 1997 to the north range of the inner court by Niall Phillips Architects.
MATERIALS: the buildings are of Cotswold stone ashlar, with some stacks of ashlar and others of brick. Some of the roofs are of lead, others are tiled. The majority of the window frames are metal casements.
PLAN: Thornbury Castle comprises an inner court with an outer court to the west, the remaining upstanding sections of which are listed separately; the inner court is entered through a gatehouse at the centre of the western range. The western range originally housed the Duke and Duchess's wardrobes, as well as lodgings; the south range originally contained the principal state rooms and private chambers, whilst in the north range were kitchens and additional lodgings. The earlier eastern range which once closed the inner court has been demolished.
EXTERIOR: the west range was never completed, but the intended symmetrical composition, with a regular rhythm of large polygonal outer towers, with intermediate turrets and a central gatehouse, can be read in the full-height tower and turret to the south, with the corresponding elements left at only two storeys, continuing northwards. The completed south tower is uncrenellated, though there is heavy machicolation to the parapet; the smaller turret formerly had a pyramidal cap. An C18 roof, with C19 half-timbering to the gable, has been added to the turret immediately to the south of the gatehouse. A moulded string-course marks the lower level reached by the buildings, with a second string-course below the upper two storeys of the completed towers. The string-course follows the heads of the mullioned two-light windows in northern portion of the range; the windows in the southern portion have hood-moulds. There are cross-loops to the bases of the major towers. A pair of sash windows has been inserted to the right of the gatehouse, as part of the C18 conversion of this portion of the building. In the gatehouse, a large four-centred arch with moulded frame is accompanied by a pedestrian entrance to the north, the doorcase being a four-centred arch with foliate carving to the spandrels, framed by a square hood on colonnettes. The presence of this small gate, beside the larger one, is almost unique in an English castle, the arrangement being more common in monastic and town entrances, and in France. The principal arch has a groove to accommodate a portcullis. The timber gates and door, with diagonally-fixed battens forming a meshed pattern, are not original. Above the openings, a banner carries the inscription: 'This gate was begun in The yere of Owre Lorde Gode MCCCCCXI The ij yere of The reyne of kynge Henri the viij, by me Edw […] duc of Bukkynghm Erlle of Hertforde Stafforde and Northampto'. Below to right is inscribed, 'Dorenesavant', the Duke's motto being, 'Doresenavant' meaning 'Henceforward'; the corresponding portion has been lost to the left of the gate. Above this, heraldic badges associated with Duke of Buckingham are displayed on shields; these, which appear elsewhere on the building, both externally and internally, are the Stafford knot, a mantle with cords and tassels dependant, a white hart, collared and chained, a swan with its neck encircled by a crown, with a chain dependant, and a fire-ball. In a central panel, a shield charged with the Duke's quartered arms, encircled by the Garter. It is thought that the gateway was originally intended to be surmounted by an oriel window. Within the gatehouse, the corners retain the lowest portion of ribs which were to have sprung to create a fan or lierne vault, beneath the current timber roof. Within the inner court, the eastern opening of the gatehouse, which is the breadth of both the principal and postern gates to the west, is framed by engaged columns. The turrets to either side of the gatehouse project as on the west front, though here they are narrower, with doors. The C16 character of the southern part of the west range, on this elevation, has been substantially affected by the steeply-pitched roof with dormers, thought to have been added in the early C18, and by the replacement of the casements with sash frames. There is a partially blocked doorway to the south of the gatehouse.
The large south tower of the west range also forms the western element of the southern range - Buckingham's 'New Building' - with a narrow stair tower with single-light windows and a doorway at the angle with the south-facing elevation. This range, overlooking the privy garden, contains the rooms designed to accommodate the Duke and Duchess of Buckingham, the Duchess's apartments being on the ground floor, with the Duke's above, in an arrangement employed in Henry VII's palace at Richmond. These are lit by double-height compass windows with elaborate geometrical profiles – the type apparently inaugurated in Henry VII's late 1490s tower at Windsor, and elaborated in his 1503 Lady Chapel at Westminster Abbey. At Thornbury, the ground-floor windows take the form of a star, whilst above, the western window is canted to a point; the five-lobed window to the Duke's great chamber, to the east, is the most impressive. The lights of the upper windows have trefoil heads. To the west of these windows, a projecting bay with canted corners, with corner windows at a high level; within this bay is a stair. The effect created by these three bay windows has been described as 'probably the most perfect grouping of its date in existence' (Buildings of England: Gloucestershire vol. 2). Between this bay and the stair tower, first- and second-floor twelve-light windows, the lights of the second-floor windows with ogee heads. The remaining windows of this elevation are a mixture of single-, two-, and multi-light mullion and transom windows with cusped and plain four-centred heads; hood-moulds are stopped by heads, or by the Stafford knot. At first-floor level, two four-centred arched door openings with carved spandrels, one in the south-face of the western tower, and the other at the east end of the range; these once gave access to the two-storey cloister which surrounded the privy garden, to the south of this range, and connected with the ducal pew in at the east end of the parish church. There are string-courses above the first floor and below the crenellated parapet; some of the decorative gargoyles take the form of the Stafford knot. Rising from the west end, a complex chimney of red brick, with geometrically-patterned side stacks flanking a central section taking the form of a concave spiral, and panels to the rim. At the east end of the elevation, the outer walls continue beyond the enclosed, habitable range with windows exposed on both sides, terminating in an irregular edge where the wall remains unfinished, or partially destroyed. The return wall is blind, apart from a substantial C19 central doorway, with a smaller blocked doorway to left, which may be part of the original design. The north elevation contains fine first-floor windows intended to serve the Duke's apartments: within the shell at the east end is a tall oriel window with blind lower lights; the form of the oriel further west has been significantly altered by restoration, which has reduced its height, and replaced the central four lights with a blank panel, though the supporting corbel, with trefoil panelling to the underside, is original. Further west, an un-restored four-light window with ogee and mouchette tracery, as on the south elevation, with a hood-mould above. The fenestration otherwise consists of small, irregularly placed windows, some dating from the C19. Between the two oriels, a stack is corbelled out at first-floor level. The stack on this side, also of brick, is if anything more elaborate than that above the south elevation, with heraldic decoration to the side stacks, the tops of which are lobed to echo the form of the largest of the compass windows, with arrow loops to the rim. A scroll at the base of the chimney bears the date 1514. The incomplete section of this elevation is crenellated; the habitable section to the west is not. The main entrance to the building is now through a C19 door at the junction with the west range; to the left is a mounting block carved with the Stafford knot.
The north range has undergone extensive restoration and rebuilding during the C19 and C20. At the centre of the south elevation, a polygonal stair tower, with regularly placed two-light mullioned windows to either side. This range has projecting wings to the north, and mullioned windows belonging to different phases. A tall window above the eastern door on the northern elevation is thought to be a C20 intervention, whilst the pitched roof rising behind the parapets, with half-timbered gables, dates from the late-C20 conversion. The principal feature of the late-C20 work is the addition of a double-height canted bay to the east end, in a C16 style, incorporating features found elsewhere in the castle.
INTERIOR: within the west range, the portion to the west of the gatehouse contains kitchens on the ground floor, with reception rooms decorated in the C19 and C20 above. To the east of the gatehouse are cellars, identified as a dungeon in the late-C16 survey. The bedrooms within this range are thought to retain few notable original features.
Each of the two suites in the south range originally consisted of three large chambers, with closets, the bedchambers being in the tower. The interior is now essentially the product of the C19 refurbishment by Salvin, with later alterations and additions. Salvin's work included some reordering of many of the principal spaces, and the re-siting of a number of features. The 1832 survey of the building made under the direction of A W N Pugin, which produced a number of plans and drawings, allows us to identify a number of the most significant survivals and changes. Salvin's renovation made the former Duchess's apartments on the ground floor into the principal public spaces; these are characterised by plain Tudor-style panelling and compartmented ceilings by Salvin, with late-C20 decoration and carpentry by Steve Edgar. A corridor runs along the north side of the range, with stairs to east and west, the western stair, with integral balcony, being Jacobethan in style. Stone spiral stairs remain within the two towers on the south front. The central room - now the drawing room - is entered through a stone Tudor doorcase, with armorial badges enriching the concave-moulded jambs, and the spandrels; this doorcase originally stood between the great chamber and dining chamber in the first-floor Duke's apartments. On the north wall of the drawing room, moved to allow for the insertion of the corridor, is an elaborate C16 Tudor-arched fireplace, with foliate carving to the spandrels, and a frieze of quatrefoil panels with armorial badges; the C19 painted panels above replace original carved panels, and there is a grate with C19 heraldic tiles. The windows of this room have roundels of painted armorial glass by Thomas Willement of 1858. The ground-floor room to the east, once the largest of these chambers, and now the library, has been reduced by the insertion of service rooms at the east end. A fireplace now stands at the east end of the library, replacing one to the east of the window. The octagonal tower room at the west end, and the room to the north of this, are now in use as dining rooms, with C19 panelling, and C19 moulded and carved stone doorcases reflecting details of the C16 building. The first floor is now subdivided into bedrooms, with a central corridor running the length of the range, the rooms being accessed through doorways with timber four-centred arches. At the east end, the great cinquefoil compass window has armorial badges studding the uprights internally. Immediately to the east is visible part of a large and complex fire-surround with carved heraldic panels and studded decoration, extremely similar to the one described by Pugin as being in the same position in the room below. A number of the other rooms retain original stone fireplaces, with Tudor arches and foliate spandrels with armorial details, including the former Duke's bedchamber in the west tower, which has a corresponding moulded stone doorcase with carving to the spandrels; one first-floor fireplace also has a concave inner moulding a frieze of linked quatrefoils.
The north range, the rooms of which would originally have been relatively plain, is thought to have lost much of its original character internally, and a thoroughgoing conversion in the late C20 providing additional bedroom accommodation has substantially altered the appearance of many of the internal spaces. However, the large kitchen to the west, now remodelled as the Tudor Hall, retains a large fireplace, with evidence of a second fireplace to the west.