The earliest remains found in Ashendon parish were some prehistoric pottery and flint flakes found in excavations off Main Street in advance of a housing development. The artefacts were not found within any features but some of the pits, post-holes and gullies that were excavated were thought to be earlier than the Roman and medieval features on the basis of stratigraphic relationships. Finds of a later date from this excavation are detailed below.
A few Roman coins are said to have been found around Ashendon in the early 20th century, Late Iron Age and Roman pottery were found in a fieldwalking survey to the north-west of Pollicott Farm and Roman and medieval pottery were found in a fieldwalking survey to the north-east of St Mary’s church. Development to the north of the church in the 1980s also uncovered Roman, medieval and post-medieval pottery and some 17th century clay pipes. More Roman activity was found in the excavations off Main Street, where pottery of this date was found in a pit along with animal bones. Saxon pottery was also found in these excavations, suggesting some settlement nearby at this period. An Anglo-Saxon burial was found in the old stone quarry, which was active in the 19th century, and from the style of the brooch found with it was dated to the 7th century AD before the widespread adoption of Christianity.
Ashendon is recorded in Domesday and was part of Bernwood Forest from before that time. 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).
There was another village in Ashendon parish in the medieval period. It was known variously as Pollicott, Great Pollicott, Pollicott Cressy, Pollicott Valence, Little Pollicott or Pollicott Bucktot and is recorded as far back as Domesday and it had its own separate manor. The remains of the village, house platforms, hollow-ways can be seen around Pollicott Farm, an earlier version of which was probably the manor house. The current house dates to the late 16th century and had a dovecote in the grounds according to a 17th century map. There is also a mound in the grounds that may be a windmill, or possibly a Bronze Age barrow, and lots of ridge-and-furrow around, the remains of the medieval ploughing technique.
A windmill is recorded in Highdown Field from the medieval period and the remains can still be seen at the highest point. It was last recorded on an estate map of 1641. This estate map also recorded the site of the manor house of Ashendon manor itself, but this has now gone. The manor is also known to have had a dovecote in the 14th century. Ashendon village was also bigger in the medieval period and the earthworks of the medieval village can be seen around the church and south of the village. The rectory was probably to the north of the church and another dovecote to the east, according to this same 1641 map. The excavations off Main Street uncovered three phases of the medieval settlement. In the 12th century the area was used as an animal enclosure but in the 13th century three dwellings were constructed. By the 14th century the area had been abandoned and reverted to pasture or orchards as no 14th or 15th century pottery was found.
The oldest surviving building is St Mary’s church, dating to the 12th century, although the tower was added in the 15th. Many of the other listed buildings in the parish date to the 17th century, including Ashendon Farmhouse and one of its barns, which has a date plaque showing 1676. East Farmhouse is dated 1692 and The Bakehouse is also 17th century.
In the 19th century there was a brickworks and lime kiln near Hill Farm. Another late development in the parish was the Quainton to Brill tramway built for the Duke of Buckingham and Chandos’ estate. The extended line was opened in 1872 and worked until 1935. The section through Rushbeds Wood has been surveyed. The Grendon Underwood to Ashendon railway was built as a branch from the Great Central Railway in the early 20th century but is now mostly dismantled. Even some of the bridges have been taken down, including one on the border with Wotton Underwood near the former Wotton station.
The most recent monument recorded in the Historic Environment Record is Westcott airfield and military site, which strays into Ashendon parish. This was the site of an airfield in the Second World War and afterwards it was turned into a rocket testing facility during the Cold War.