It was built in 1839 on the site of an 11th-century Saxon church, and has been designated by English Heritage as a Grade II listed building.

[2] In the early 11th century, a church was built on the site of a Roman fort erected to guard a crossing over the Ouse, below which the river was navigable.

Concluding that it was impractical to extend the old church, the rector, Peter Guerin Crofts the Younger, had it demolished and a new one built on the site.

[13] The tower, placed centrally at the ceremonial west end of the church, projects forward of the front wall,[1] and contains three 18th-century bells by John Waylett, one of which was re-cast in 1886.

Mark Antony Lower, founder of the Sussex Archaeological Society, called it a "modern brick structure, which we cannot commend, as it is a kind of hybrid between a castle and a barn",[17] while the 1868 edition of Murray's Handbook for Travellers in Kent and Sussex was blunter, calling it "modern, and ugly".

[18] Internally, cast iron posts support galleries with painted panelled fronts which extend for the full length of the nave on each side.

[20] The two-manual organ, built by Bishop in 1882 and rebuilt by Morgan & Smith of Brighton in 1927, stands in a chamber in the apse.

The inscription reads "Clauditur hic miles Danorum regia proles Mangnus nomen ei mangne nota progeniei; deponens mangnum se moribus induit agnum, prepete pro vita fit parvulus anachorita", which translates as "There enters this cell a warrior of Denmark's royal race; Magnus his name, mark of mighty lineage.

[23] The verse plays on the anchorite's name being the same as the Latin word for "great" or "mighty", magnus, here spelt mangnus.

[26] A theory long since discounted suggested he should be identified with Magnus, the son of King Harold II, who fled to Ireland after the Norman Conquest and later took part in incursions against England.

[28] Designed by Philip Currey and made by local mason John Strong in a neo-Gothic style, it takes the form of an octagonal drum with marble ribs tapering to a spire, topped with a tabernacle and a cross.