St Mary's church East Carleton is a medieval structure extended and modified by centuries of repair and restoration. It is most likely built on the site of an earlier Anglo Saxon church recorded in the Domesday survey of 1086. Karletuna (East Carleton) 2 churches with 38 acres (glebe). St Peter's church which was also a medieval structure and of which only a small part of the wall remains being on the site of the other Anglo Saxon church recorded in the Doomsday survey of East Carleton. East Carleton previously formed two parishes each having its own church, St Peter's and St Mary's. The ruins of a wall belonging to St Peter's church can still be seen today in the graveyard.
The oldest part of St Mary’s church is the North aisle which has its origins in the thirteenth century about 1249 or a little earlier. The south doorway is of the Decorated period showing that the church was probably extended by the addition of the central nave and chancel in the 1300’s. The three bay arcade has round piers of 1881, supporting 14th century chamfered arches, which again points to the church being enlarged and extended in the 1300’s. The tower was probable built around 1500 or the late 1400’s and the arch has fine mellow Tudor brickwork. The circular stair turret also dates from this time and so St Marys probably fits the pattern of building and enlargement that went on in parish church almost up to the Reformations but from then on it was a process of deterioration and decline until the great Victorian restoration of our parish churches in the 19th century.
The St Mary's church of today has modern electric heating, a useful kitchen area and an outside toilet. Today St Mary’s is one of five churches within the Swardeston Group of Parishes looked after by one vicar. Not only is the church used for religious ceremonies, services and celebrations but also for social events such as coffee mornings, the village fair and used as an exhibition venue for the Open Gardens event.
January 1845-A serious theft took place in the parish when one, Dersley, stole the lead off the church roof. He was prosecuted by the church wardens, convicted and sentenced to be deported for ten years, a pretty stiff sentence. The prosecution cost the Parish £6.6s 6d which was paid out of the church rate.