[4][5] Its origins lie in a manor whose land lay within two exclaves of the parish of Ashington within the Rape of Bramber, one of the six ancient subdivisions of Sussex.

[6] The settlement's church was built on a rural site, considered a "picturesque setting",[7] at an unknown date during the Norman period.

[11] An article published in volume 38 of the Sussex Archaeological Collections (1892) dated it to 1150–1180 and attributed its construction to the monks of Sele Priory at nearby Beeding, although a wide-ranging study of Sussex church architecture 15 years later suggested a date of c. 1070 for the nave and chancel arch—partly based on the lack of buttresses.

It was shortened, the east wall was rebuilt with square masonry blocks, and a Decorated Gothic window was inserted.

The church also gained an aumbry and a piscina at this time,[2][8] and some richly decorative Norman-era masonry arches were inserted in the exterior walls on the north and south sides.

[2][8] Although it is common for Norman churches to have carved or painted representations of human faces or figures,[19] Buncton's was a very unusual example: an 8-inch (20 cm) sculpture of a person of indeterminate sex showing its genitals.

[20] It was similar to a Sheela na gig—typically a smiling naked woman with exposed genitalia, common in churches in the Republic of Ireland but rarely seen elsewhere, and reputedly associated with pagan sites, Celtic fertility rites or medieval anti-immorality teaching.

[20] In December 2004, an unknown person entered the church and destroyed the carving with a chisel, smashing it into dozens of pieces.

[8] It is built mostly of flint, in common with many Sussex downland churches; some stone rubble and masonry is also visible, and recycled Roman tiles can be seen.

[3][16] The outside of the north wall of the chancel incorporates a pair of Romanesque-style[1] Norman-era blocked arches, described as "extraordinary" by Nikolaus Pevsner (who dated them to c.

[1][2][4][10][11][21] The chancel measures 14.5 by 20 feet (4.4 m × 6.1 m): these unusually short proportions are evidence of the work carried out in the 14th century to cut its length back.

Square plinths with decorative moulding support shafts with unusual capitals which have abaci with such extensive chamfering that they are almost circular.

[24] The parish, whose legal name is Wiston with Buncton, covers those two villages at the foot of the South Downs and a large rural area between the A24 and A283 roads.