St Mary's is a twelfth-century foundation, but all that remains of the twelfth-century church, probably built in two stages, are the pillars on the south side of the nave, the projecting corbel on the south side of the chancel arch and the priest's door on the south side of the chancel.
In 1216 St Mary's was burned by King John, with many of the villagers who had taken sanctuary in the church still inside. In 1327 the church was damaged, probably by fire, when the castle was also destroyed. In 1705 the nave roof was yet again destroyed by fire from the open braziers heating the church.
St Mary's was re-roofed and restored in about 1840, and then enlarged in 1870 by R.J. Johnson for the squire of Mitford. A new chancel arch was raised, the chancel repaired and new east window installed. A new reredos was fitted in 1883. In 1984 the nave and chancel were re-roofed and the woodblock floor replaced by York stone.
the ancient bell now hanging beside the main door is believed to be from the twelfth century and to be the oldest bell in Britain. A peal of 13 bells was hung in 1876, operated from the baptistry by ropes. The two-manual Nicholson organ of 1878 was recently restored. The Mitford window in the south aisle is by Kempe (1895)
There is a fine tomb - of Bertram Reveley, who died in 1625. The lych-gate was built in 1889.