Sefton is a large church mostly of the appearance of late Perpendicular, constructed under three successive rectors of the Molyneux family from 1489-1557. The steeple, line of the previous N aisle and a NE chapel with a double piscina and tomb niche was incorporated into this building. At the E end of the S aisle are a number of architectural fragments, some of which are Romanesque.

Sefton appears in the Domesday Book where the total tax assessed was 6 converted carucates units. The lordship in 1066 was held by five thanes under the king and in 1086 by Roger of Poitou. The parish is first documented as exisiting independent of Walton (the parish that covers much of modern Liverpool) by 1203. In 1291 the rectory was assessed at £26, 13s, 4d, and the patronage was held by the Molyneuxs until the Reformation.

Measurements of the fragments concentrated on the details that could be compared. There appears to be a doorway of at least two orders: a larger and a smaller order of bases, shafts, and waterleaf capitals. It would appear that two of the smaller and one of the larger capitals, two of the larger and one of the smaller bases, and some parts of each size of shaft have survived. The surviving voussoirs suggest a simple rolled arch. The fragments may have been a doorway retained in the 14thc church, destroyed in the Perpendicular rebuilding programme that harmonised the building. Judging from their nature, it would have been strikingly Early Gothic in appearence (akin to some work found in Cistercian Abbeys such as Furness). But the consistent use of the waterleaf type qualifies it as Romanesque. If the parish was indeed recently formed when it was documented in a tithe dispute of 1203, this stone doorway would fit well into the decade or so previous to that date.

A window at nearby Ormskirk church is strikingly similar to the fragments. It is possible the smaller Sefton fragments were a window, and the larger fragments a doorway.