The following is a summary of the church’s history and structural evolution.

Hailes’s church, which has no known dedication, is first mentioned in record sources as early as 1114. However, although Domesday Book (1086) offers us no evidence of it, there are good reasons to think that it was of later Anglo-Saxon origin, founded by the priests of the important minster at nearby Winchcombe. Nothing survives of that original church at Hailes. The oldest surviving part of the present one – its nave – was not built until at some time between 1138 and 1153 (the period of civil war in King Stephen’s reign, often called ‘the Anarchy’). Its chancel, of unknown shape and size (but undoubtedly narrower than the nave), was demolished in the 13th century, when the present, atypically wide one was built. At the same time, the nave’s original doorways and windows were replaced with the ones that still exist today. The chancel arch, too, was replaced (but not the 12th-century capitals and engaged columns on which it sits).

It is not possible to say for sure if these major changes were made before or after 1246, when the church was given to the Cistercian abbey founded a short distance to the south of it by Earl Richard of Cornwall, King Henry III’s younger brother. The first of the two phases of wall-painting (for which the church is internationally renowned) came after this extensive rebuilding campaign: little of it survives, but its high quality is shown in the magnificent representations of St Catherine and St Margaret near the east end of the chancel.

Early in the fourteenth century, by when the church was certainly in the abbey’s hands, there was a major renovation of the chancel. As a result, its 13th-century windows were all replaced. The eastern two were filled in (thereby concealing the two female saints, until they were rediscovered at the start of the 20th century), and stone seats for three priests were set into its south wall. These alterations were soon followed by the second phase of wall-painting, which is often said to belong to the period c. 1320-30 but may be a decade or so earlier. (The geometric patterns in the chancel and most of the scenes and figures in both nave and chancel are thought to have been painted during this second phase.)

When the abbey was suppressed in 1539, on Henry VIII’s orders, its ownership of Hailes’s church ended. Before the abbey’s foundation (1246) it had been an independent parish church, and the church at Didbrook (less than a mile away to the north) had been its chapel. However, throughout the life of Hailes Abbey Didbrook’s church had had to act as the parish church for all of Hailes and Didbrook. This is because Hailes’s was no longer accessible to parishioners, being enclosed inside the monastic precinct and used solely by pilgrims and other visitors to the abbey. (It is thought that the church was where confession was heard and absolution given before such people were allowed to approach the holy relics in the abbey church.) However, from 1539 onwards the two churches’ roles were the reverse of what they had been until 1246, with Hailes’s becoming Didbrook’s chapel (as it still is).

Such a reversal is very rare, but the circumstances were undoubtedly exceptional. It helps to explain why Hailes’s church, which in the 12th century was rich and influential in the Winchcombe area,   is nowadays not used much for services and, understandably, is at the back of the queue for scarce parish funds when its fabric and furnishings need expensive attention. Now that the parish has been enlarged to include Stanway and Toddington, too (which themselves have large churches and small congregations), the need for regular fund-raising to support Hailes’s very precious church is even more urgent – hence the essential role of the Friends.