The church was rebuilt in 1846-7/8. Drawings survive of both the chancel arch and the S doorway prior to the 19thc. building, which show that both were of 12c. date. Various carved stones from these were re-used in the doorway to the vestry at the NW corner of the church. Other fragments have been incorporated into the E interior wall of the vestry. An ornate baptismal font of possible late-12thc. date is located in the SW interior of the nave. Various other medieval stones are also preserved within the church. Outside, re-used in the churchyard wall near the gate leading to the rectory are a series of chevroned voussoirs and other carved stones.

This part of England is not covered in the Domesday Book, but it is clear from various early carved stones that there was a religious centre at Aspatria before the Norman Conquest. A 10thc. date for the earliest of the Aspatria carvings has been proposed by various writers. The association of Aspatria with St Kentigern (also called St Mungo) is also likely to have occurred at an early date, possibly as a result of Kentigern’s journey through this part of the country in the 6thc. It is thought that the name ‘Aspatria’ (formerly ‘Aspatrick’) derives from Gospatic, Earl of Northumbria. Gospatric was deprived of his English lands in 1072 and eventually moved to Dunbar in Scotland. During the reign of King Henry I, Gospatric's son Waldeve (or Waldeof) became the first lord of the barony of Allerdale below Derwent (i.e. Allerdale above the Derwent River). According to the Chronicon Cumbrie and the ‘Memorandum on the descendants of Waldeve son of Earl Gospatric, lords of Allerdale, c. 1275’ the advowson of the church of Aspatria was given by Waldeve’s son Alan to Carlisle Priory (Reg. of St Bees, pp. 493-4 and p. 531). The priory of Carlisle was founded by King Henry I in 1122 and Alan appears to have died in the early 1150s. From that time on, the church was rectorial. In one of Alan’s charters, in which he gives certain lands in Aspatria to St Bees Priory, ‘Gamello dapifero de Aspatric’ appears as a witness (Reg. of St Bees, p. 50 no. 22). This may infer the possibility of a residence of Alan somewhere within Aspatria. Alan was succeeded by Alice de Rumilly, who died about 1215.

The angular basketwork used on the label of the former chancel arch can be compared in Cumbria to that on the 12thc. loose tympanum at St Bees. Basketwork decoration, though more advanced at Aspatria, was used as a decorative feature in Cumbria before the Romanesque period, as can be found on loose stones at Beckermet (St John's Church) and Workington (St Michael's Church).

The closest comparison in Cumbria for the baptismal font is the one at Crosscanonby, which may have been carved by the same sculptor. Outside of Cumbria, the general form of the font can be compared with several in Cornwall, such as that in the church at Bodmin where a date in the late-12thc. has been put forward by others. Whether the Aspatria font is late-12c. or early 13thc. is not certain.

The form of cross on the two cross heads built into the churchyard wall is similar to that found in Cumbria at St Bees Priory on a grave end upright (kept at present inside the church). It is also found further afield, as for example on a coped grave cover in the churchyard of St Andrew's Church in Bugthorp (Yorkshire). This form of cross seems to date to no earlier than the late-12thc.

Many of the other surviving carved stones at Aspatria appear to come from either the chancel arch or the original S doorway. There is one chip-carved stone however, now in the vestry wall, which is not shown specifically in either the chancel or doorway print. Although it's original use is uncertain, it’s shape and size could suggest a former use as an impost or part of a stringcourse.

In the print showing the S doorway before it was taken down, the bases are depicted with claw-like triangles hanging down over a bulbous form. This type of base is unusual, but there are a number of similar bases still in existence within Cumbria, as at the churches of Bridekirk, Isel and Torpenhow.