The earliest surviving reference to Knaphill is as 'la Cnappe' in 1225. 'Knap' means 'at the top of the hill' so the name used today is a good example of tautology meaning as it does 'at the top of the hill hill'.
Knaphill formed part of the ancient parish of Horsell. Horsell was originally a chapelry of Woking but it also formed part of the Manor of Pyrford, which probably explains why Horsell is not recorded in the Domesday Survey in 1086. Therefore, Knaphill along with the rest of Horsell, was probably part of the lands granted to Westminster Abbey in 956 A.D. Horsell was certainly the property of the Abbot of Westminster by 1278 but would have passed to Henry VIII when he dissolved the monasteries in 1530s.
The property, including Knaphill, was owned by Denzil Onslow by 1678 and it continued to be held by the Onslow family into the 20th century.
The Basingstoke Canal was constructed south of Knaphill and opened in 1794 and the railway came in 1838, the nearest station being Brookwood. Knaphill developed slowly but not initially as a commuter village and many found employment locally. A prison was established here in 1859 but it was later converted into army barracks.
The soils around the settlement proved ideal for the establishment of garden nurseries and these employed large numbers of workers. The earliest nursery here was probably founded by John Waterer in the 1760s. In 1809 the nursery started to specialize in rhododendrons and the business continued to be owned by the Waterer family until 1976.
The first school was opened at Knaphill in 1877, a measure of the growing population, and the church of the Holy Trinity was built in 1907. There has been a great deal of house-building adjacent to Knaphill in modern times and the area continues to offer attractive homes for those who wish to work locally or in London.