By the 13th century Cropredy was associated with the legend of Saint Fremund, a Mercian who was said to have been martyred in the 9th century. Fremund's relics are supposed to have been moved from Offchurch in Warwickshire to Prescote, where they were lost for a time and then rediscovered and moved to Cropredy. They were then moved to the Augustinian Priory at Dunstable, probably in 1207, but an association with Fremund remained at Cropredy. There are records of gifts to a chapel and shrine to the saint here in 1488 and 1539, and a chantry priest serving in St. Fremund's chapel in 1489. During the English Reformation under Edward VI the Crown sold the chapel and its contents in 1549 and it was probably demolished. No trace remains, its site is unknown and it is not clear whether the shrine chapel was at St. Mary's church or elsewhere in the parish.