The nave, originally aisleless, and tower are C12, though the latter was heightened twice, around 1200 and 1500, the date of the stone spire, which was later altered.  Aisles were added around 1300.  The east end and Frewen mausoleum are C19.  There is good C17 woodwork.

Northiam is built around a green with weather-boarded houses, which are reminiscent of nearby Kent.   From 1583 to 1914 a member of the Frewen family or their heirs the Lord family, was rector, except for a brief period in the late C17.  Their Puritan sympathies are shown by the name of the most eminent member, Accepted Frewen.  However, like most of his relatives, he conformed and in 1660 became Archbishop of York.

The C12 nave was sizeable, but the quoins of the west wall show it had no aisles.  The bottom stage of the tower is of the same date, with square-headed north and south windows.  Their round-headed rere-arches are set in large round-headed wall-arches with concave abaci.  The next stage of c1200 has single lancets beneath three grouped and pointed arches, like Herstmonceux.  The restored pointed west doorway, with mouldings and angel-stops, is rather later in the same century.  The arch into the nave is like the wall-arches, but a plain pointed arch within it matches the work of c1200 and was probably inserted as reinforcement when the bell-chamber was added.

Shortly before 1300, the south aisle was added with a lancet near the east end.  The arcade and trefoil-headed lancets of the clerestory reveal the date.  The latter look renewed, but though Sir Stephen Glynne in 1868 called their predecessors ‘modern’ (SNQ 16 (Nov 1967 p340), something similar is shown on the Sharpe drawing.  The round piers and double-chamfered arches of the arcade are standard, but the former are thicker with more deeply cut abaci than the superficially similar north arcade.  The VCH calls it late C14 (9 p275), but such are the similarities between the two that the difference in time is short; more probably they date from either side of 1300.

Judging from the Sharpe Collection drawing (1804), the previous chancel was C13 with a south lancet and doorway.  The chancel arch is said to have been similar to the arcades though larger (Horsfield I p517) and was thus presumably C13 or C14.  Other C14 work included the east window with intersecting tracery and square-headed south windows, whilst a lean-to north chapel is described as C14 in an ICBS application of 1833. 

In the later C14 square-headed windows with pierced spandrels were inserted in the south aisle, with a large stone porch with a double-chamfered arch and a similar doorway.  Both are offset to the west because of an altar against the east wall (2 p139).  In the north aisle only the square-headed west window and the moulded doorway are C14.  Later windows in both aisles included a C15 east window of the south aisle with panelled tracery and two with depressed heads in the north aisle, probably inserted after 1500.

It is tempting to relate this C16 work to a more conspicuous change, the addition of a top stage and a spire to the tower, built of a lighter stone.  The bell-openings are square-headed and have two lights except a single south one, which allows for an octagonal stair-turret rising above the battlements.  The most famous feature of Northiam is the octagonal stone spire, one of only four mediaeval ones in the county and by some way the tallest.  New diagonal buttresses were added to support the additional weight.  A precise date is provided by a bequest in 1505 towards the cost of a new steeple and bell-chamber (SRS 43 p251).  The spire has twice been altered, first in 1773 - an inscription of that year calls it ‘newly erected’ (Langdon p197).  The angles of the spire for the first five feet are roll-moulded, so this part may be original.  This spire is shown on the Sharpe drawing, but is still shorter than today, as it was heightened by a further 10 feet in 1860 (2 p140).  To achieve an even taper, most of the existing structure must have been replaced, but this is not obvious.

The second heightening of the spire was not the first C19 change.  There were plans to rebuild the eastern parts to create more space in 1833, when an application to the ICBS was made in the hope of gaining worshippers from the nonconformists (1 p2).  The chancel (and chapel) were replaced between 1837 and 1847 by a large aisled one as long as the nave with a flat ceiling and big lancets, except for a four-light east window.  The architect was S Smirke (ICBS).  The aisles are broad, to allow for galleries, and the chancel arch was not replaced, though the chancel arcades resemble those of the nave.   Smirke retained most fittings (see below), perhaps because the Frewens had presented many, particularly Thankful Frewen in 1638.

The Frewen family vault was moved during this work and Smirke added a large mausoleum to the north in 1846, with Perp detail and much heraldry (WSRO Ep II/27/55).   The heraldic decoration of the roof is by T Willement and was supplied in 1847 at a cost of £53 9s 3½d (Willement ledger). Nothing else was done, apart from the alteration to the spire in 1860, until 1878-79, when A Smith (WSRO Ep II/27/200) repaired the stonework and replaced the ‘modern’ south clerestory windows noted by Sir Stephen Glynne (SNQ 16 ibid).  Smith replaced the aisle roofs, but that of the nave looks original.  In 1887 he did some further work on the church, assisted by C Smith (B 52 p455).  More recently there were further repairs in 1966 (ICBS), when the architects were named as J D Wylson and R C Cox.  In fact Wylson was already dead, so his former partner Cox must have been solely responsible.

Fittings and monuments

Altar rails: Arcaded and arranged round three sides, 1638.
Box pew: (North aisle) A single survival of the C18 seating.
Brasses:
1.  Robert Beuford (d1518), rector.  Small and vested for mass. Of the symbols of the four evangelists, only the ox of St Luke and the lion of St Mark in roundels remain.
2.  Nicholas Tufton (d1538) Though a knight, he wears civilian clothes.  His family held the manor of Northiam (Mosse p110).
Chandelier: (Nave) Dated 1727.
Communion table: 1638, with bulbous legs.
Fonts:
1.  Dated 1931, copying C12 work, by A S Haynes (CDG Feb 1931 p81).
2.  C18 marble fluted bowl on a baluster.  Ejected in 1931 and put back in 1968 (1 p16).
Glass:
1.  (North aisle and mausoleum) C17 heraldic and some of 1846 by T Willement (Willement ledger).
2.  (East window) M C F Bell of Clayton and Bell, 1928 (DSGW 1930).
3.  (South aisle, second window) Kempe and Co, 1921.
4.  (South aisle, east window, partly concealed by vestry) M Travers, c1937 (Warrener and Yelton p322).
5.  (North transept, north window) P W Cole, 1953 (ESRO Par 431/4/1/11).
Monuments:
1.  (Various) Mediaeval stone tomb-slabs.
2.  (Mausoleum) To the Frewen family, including some moved in 1846.  Most are wall-tablets and extend to the late C20.
3. Anne Frewen (d1844) by W Behnes (Roscoe p92).
Panelling: (East end) 1638.
Pulpit: Plain panelled and C18.
Royal Arms: (West wall). Painted, of Queen Anne.

Sources

1.  W L Davis: The Church of St Mary Northiam, 1972
2.  W H Godfrey: St Mary Northiam, SNQ 4 (Feb 1933) pp138-40

Plan

Measured plan by W H Godfrey in VCH 9 p275