St Mary's Church, Polstead, is a Grade 1 listed medieval church in a superb natural setting, overlooking parkland and the Box valley towards Stoke by Nayland. The building incorporates Norman and Anglo-Saxon elements and building material from a nearby Roman villa. The site goes back to St Cedd's legendary preaching under the Gospel Oak, in the grounds of Polstead Hall, circa AD 653.The church has a wonderfully peaceful atmosphere which is remarked on by all who visit it. It is included in Sir Simon Jenkins' One Thousand Best English Churches.
The church shows signs of development over many centuries. The existing building is thought to have originated in a small Norman church, now incorporated in the west end of the nave. A fine, well-preserved Norman arch, which appears to have been the main entrance door, is in the base of the bell tower. Romanesque brick arches on delicate stone columns flank the clerestoried nave, incorporating blocks of tufa, thought to have come from the site of a nearby Roman villa.
However, the bricks which appear to predate the standardisation of bricks in the seventeenth century, show signs of heavy restoration, perhaps even rebuilding, when extensive repair works were carried out in the late nineteenth century. An impressive perpendicular arch leads to the chancel of late perpendicular design. North and South side aisles are later additions, perhaps contemporary with the tower, which is topped up by a later stone steeple, one of only two in Suffolk. The peal of six bells was rehung in 1955.
Seating in the church is mainly pews, mostly of late nineteenth century design, but substantial and blending well with the atmosphere of the church. Modern chairs augment the seating in the side aisles and at the back of the church. Armorial shields of past patrons are on the end pews in the nave. There is a late nineteenth century reredos behind the seventeenth century holy table, which is surrounded on three sides by a very fine seventeenth century altar rail. The oak pulpit is of twentieth century design. Around the South aisle panelling up to window height seems to be all that remains from pine box pews, presumably removed during the nineteenth century repairs. In a few places, small areas of medieval wall paintings, of archaeological rather than aesthetic significance, have been uncovered. There is a fifteenth century brass on the floor in front of the chancel. The most notable wall monument is a stone monument to the Brand family, then owners of Polstead Hall. There are also late eighteenth and early nineteenth century family hatchments and two mid nineteenth century charity memorials. The organ was installed in 1838 and is well suited to the acoustics of the church.
The churchyard, which surrounds the church is bordered by the grounds of Polstead Hall and the "horsecroft" or old deer park, contains a number of eighteenth and nineteenth century tombs to the north. To the east are mainly nineteenth century tombs and the fine war memorial (a copy of the cenotaph in Whitehall); and to the south and west more modern tombs stretching down the hill towards grazing land. Entrance to the church is now by the South door, which provides a level approach and enjoyment of the magnificent view and avoids awkward steps at the North door. A toilet is available in the churchyard shed adjacent to the South entrance.