A Roman stone-lined trough excavated for a pipeline trench north of Stonehill was thought to have been a cist grave but did not contain any human bone. It may, instead, have been for some kind of industrial purpose. The pottery found inside it dated the structure to the 3rd century AD. A Roman road running north-east from Akeman Street seems to have passed through this parish.
North Marston is recorded in Domesday and Saxon artefacts were found in the garden of 18 High Street. A 10th century document tracing the boundary of the manor of Winslow mentions a settlement in North Marston parish called Heort Hill, which may be that marked as Harts Hill on an 16th century map and now known as Windmill Hill (there is a mound of a later windmill in this field). The document also mentioned Heortmere; this settlement probably continued into the medieval period as the Winslow court rolls mention a hamlet near a lake or marsh and the field often has a pond in its lowest part when flooded. The other settlement mentioned in the 10th century is Stapelum and this name survives in Staples Farm and Staples Corner. By the time the fields were enclosed in the 18th century, these hamlets no longer existed.
North Marston was also part of Bernwood Forest from the Saxon period. Bernwood had been a hunting forest from the time of Edward the Confessor. It grew to its largest extent under Henry II. The whole area was not covered by woods; in the medieval period a forest was a place where deer roamed for hunting and so included open land, villages and fields. All those who lived in the forest were not allowed to hunt or even gather wood without a special licence from the king. Bernwood Forest was finally disafforested in the reign of James I in 1635, although it had been shrinking in size since the time of King John (1199-1216). A deer park mentioned in 1202 in North Marston cannot be located.
The medieval manor house is thought to have been somewhere around Manor Farm. An 18th century barn that was demolished for redevelopment of the site was based on stone footings, probably reused medieval masonry. A medieval moat, known as the Gentleman’s Fishpond, is also known south-east of the church and that might have been the site of a manor house, although it is thought locally to have been the site of the old vicarage. There is a lot of ridge-and-furrow in the fields around North Marston, the remains of medieval farming.
John Schorne’s well in North Marston was said to cure those who drank its water. The pilgrim badge of John Schorne’s well was the devil in a boot, as this was said to be one of his miracles. John Schorne was a rector of North Marston in the medieval period, he died in 1314. Pilgrimage was one way to show religious devotion in the medieval period. There was a shrine to him in St Mary’s church that was later moved to St George’s Chapel, Windsor. The church itself is 13th century in date, though it was added to in the 14th and 15th centuries.
The first mention of a watermill in the area is 1291, on the border with Oving parish. It may have been in the vicinity of Little Mill Ditch or Mill Ditch, but its exact location is unknown. There are records as far back as 1472 of a windmill in the parish. It may have been on the site of a low mound that could be a windmill mound in Little Mill Field. This was probably moved to Knappies Close in the 19th century. North-west of the church the base of a 19th century smock mill has been identified and recorded by archaeologists. There was another windmill on Windmill Hill near Manor Farm in the medieval or post-medieval period and Old Mill Knob is recorded in the 18th century so was probably the site of another.
Of the standing buildings in the parish the oldest, apart from the church, is Manor Farm, which dates back in parts to the 14th century and is cruck-framed. It was extended in the 16th and 17th centuries. In the 13th century the building on this site belonged to St John’s Hospital, Oxford, but by the 19th century Magdalen College, Oxford was the owner. Foundations of an earlier building were found underneath 4 High Street during renovation works; the current one dates to the 17th century. Other listed buildings in the parish date from the 16th, such as Burnaby House or 3 High Street, to the 18th century, such as Moreton Cottage or The Bell.