A C12 cruciform church with a crossing tower and a fine south doorway.  The chancel is C13 and so was the north aisle (now gone).  The nave was lengthened in the C19.

East Dean is a remote but sizeable Downland village.  The church was probably started in the C12 and from the first is likely to have had a cruciform plan with a central tower, so it was a church of some consequence.  No window is apparent, but the west and east walls of the transepts almost certainly survive and so may the core of the crossing arches and lower part of the tower, despite alterations (see below).  The nave is taller and broader than the chancel and a fine late C12 south doorway is set in a thicker section of walling between two buttresses, probably to give greater depth to its pointed head, which has three recessed orders, though the later porch spoils the effect.  The two outer orders are roll-moulded and rest on shafts with high bases and weathered foliage capitals; the third is broader and chamfered.  In the C13 a north aisle was added, though only the remains of a two-bay arcade survive.  It had pointed arches and a square west respond, and an arch similar to the arcade led to it from the north transept.
  
The chancel appears to date from the early C13, for despite later rebuilding that included the east end, the form is likely to be original.  This applies, in particular, to the rere-arches of the side-lancets lack, which lack scoinsons and are the best indicator of date.  A blocked square-headed south west lowside is best seen from inside.  The upper part of the tower is likely also to be C13 and it probably had no predecessor, as it would have been the last part of the church to be completed.  It has a pair of lancet -openings to the east; the single south and west ones are similar.  Though weathered, the head of the west one appears trefoiled, suggesting it is C14.  A drawing of 1795 (VCH 4 p195) shows a larger window to the north with definitely C14 tracery, so the present one, which is like the eastern one, is not old.  The top has also been modified - today it is flat with battlements, but the Sharpe Collection drawing (1805) shows a broach spire.  Peat and Halsted claim (p68) that the original C13 heads of the crossing arches survive above the later ceiling.  The present arches are plastered and apparently post-Reformation.  An oddity is the two single-light south nave windows with shouldered heads, though with pointed rere-arches.  Such windows are generally C13, but unusual in churches.

The side windows of the transepts date from more than one period in the C14.  The east one of the north transept has three stepped lights and is perhaps around 1310.  The south transept has a single trefoil-headed west lancet and a restored east window, of about 1340, with three trefoiled lights and a head of three sharply pointed trefoils, the two lower ones upside-down.  A trefoil lancet in the blocked west arch of the north transept is C19.  The aisle itself may have had C14 windows, assuming those set in the blocked arches of the arcade originated there.  One is a single trefoiled light, the other has two lights with a quatrefoil in the head.  A reset pointed doorway is C13 or C14 with a four-centred rere-arch that is C15 or C16.  This could indicate when the aisle was removed, for a north doorway would not have been needed after the Reformation for liturgical purposes.

Post-Reformation work, though extensive, is hard to follow.  The tower was repaired, with a brick south west quoin and a clumsy south east buttress, extending to ground level.  The bell-frame dates from 1655 (Elphick p210), which may give the date of the other work, including the crossing arches in their present form – three are round-headed and slightly chamfered, whilst the broader west one has a segmental head.

The church was restored in 1870-71 by two architects.  E Christian did the chancel (Clarke papers) and, for the parish, the clerk of works at Chichester cathedral, J Marshall (ibid) restored the rest.  He was also a contractor and was thus probably cheaper.  Christian replaced the chancel roof and rebuilt the east wall with a triplet of lancets, though the segment-headed rere-arch may be old work reset.  Most stonework was replaced.  Marshall replaced much stonework and the roofs, rebuilt the end walls of the transepts and added a south porch.  He also extended the nave by 10 feet to the west (Peat and Halsted ibid).  Curiously, Peckham calls this extension C13 (1 p34).

Fittings

Aumbry: (Chancel north wall) Square-headed and probably C13.
Font: Plain octagonal, probably C17.  It rests on what seems to be a large upside-down late C12 scallop capital, perhaps displaced from either the crossing or arcade.
Font cover: C17, with an open arched top.
Piscina: (Chancel south wall) Only a square recess remains, into which probably a piscina was fitted.

Source

1. W D Peckham: East Dean (Near Chichester), SNQ 10 (May 1944) p34

Plan

Measured plan by W D Peckham in VCH 4 p96