There are at least two possible reasons. Firstly it may well have been rebuilt on the site of an earlier church founded here in Roman times. This plan shows how it fits into the Roman street pattern.
A second possibility is that the present church was built by the owner of an Anglo-Saxon manor house which may have stood in or near the abandoned Roman town.
Certainly a church stood here in the reign of King Edward the Confessor (AD 1042 - 1066). He gave the manor and the church of Caistor to the Abbey of Bury St Edmunds. This probably accounts for the dedication of the church and the village to St Edmund.
The earliest part of the church, the nave, is over 900 years old. Its south-west corner, at the rear of the building next to the tower, is made from red tiles robbed from the walls of the Roman town. The Roman tiles are very similar to the red Tudor bricks of the early 1550's, made over 1300 years later. The Tudor bricks are, however, not so long and a little thicker. The original round-headed windows of the nave have been blocked up and replaced over the centuries and are now no longer visible.
The doorway dates from the 1300's. When you enter the church you will see the superb stone font, carved with religious symbols and the arms of Edward the Confessor (left) and St Edmund (right).
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