Pewsey is very much the capital of the Vale of Pewsey and is the commercial centre for a large rural area. The parish stretches across the vale from the Marlborough Downs in the north to the scarp slope of Salisbury Plain in the south; the highest point on the Plain is 221 metres. Thus the geology is chalk in the north and south with greensand in the middle and alluvium in the watercourses. There is also a small area of clay with flints on Martinsell Hill. The river Avon flows through the Vale and is joined by the Ford Brook to the north of the village. The local roads were not turnpiked and there was only local traffic until the 20th century. Access to more distant markets was provided by the Kennet and Avon canal from 1810 and the railway from 1862. Before this the village was an agricultural centre with few trades not connected with farming.
The whole area is set in an ancient landscape and within the parish there have been finds from the Paleolithic period onwards, and there are the remains of prehistoric field systems and ditches. On the top of Martinsell (289 metres) is an Iron Age fort covering 32 acres, with associated barrows and enclosures. There was early Saxon occupation here and a 6th century cemetery with over 100 graves has been excavated at Black Patch on the lower slopes of Salisbury Plain. This overlays an Iron Age domestic site indicating that there has probably been continuous occupation in this favoured area for around 2,000 years or more.
The early Saxon settlement was Pagan but later a Saxon church, probably of wood and thatch, was built here. Apart from the impressive defensive site of Martinsell, the early domestic occupation sites seem to be close to the river and on the slopes of Denny Sutton Hipend, a spur of Pewsey Hill. The church was built close to the river and would have been surrounded by the village but the present village lies mainly to the north of it. By the 19th century Pewsey was a royal estate, owned in the latter part of the century by King Alfred, whose statue adorns the centre of the village. The estate descended in the Saxon royal family until 940 when it was given to the abbey of St. Peter at Winchester. At this time the estate boundaries were very similar to those of the modern civil parish. We know that there was a church here at the time of the Domesday Book (1086), as Rainbold the priest held some land here. There was a fair sized settlement with arable land for 24 plough teams and 7 mills on this part of the river Avon. Using modern interpretations of families recorded at Domesday we can estimate that there were probably between 370 and 400 people living on the Pewsey estate at this time.
Medieval Pewsey had a substantial population but never developed as a town, doubtless because it had no market; the nearest was at Upavon. In 1377 there were 267 poll tax payers (people aged over 14), which could indicate a population of between 400 and 500. It is likely that there were settlements at Southcott, Kepnal and Sharcott from the 13th century and a hamlet at West Wick from an early period. Agriculture was all important with arable fields on the chalky loam in the south, pasture on the greensand to the north of the village, and rougher grazing on the hills. There were still four mills in the 13th century; at the west end of the High Street, the sites of Jones's Mill and Buckleaze Mill, and at West Sharcott. At this time there were many small farmsteads, held by tenants, in what is now the village centre. These occupied the present High, River and North Streets and would indicate that the centre of population was shifting from around the church.
By the 16th century a new rectory had been built, believed to be the core of the present Court House, and an inn is first mentioned in the 1530s but by the late 16th century there were also several ale houses here. It is likely that settlement was extending beyond the central area of the present village and certainly by the 17th century there was a settlement on waste land, called Bowling Green, that was later named World's End, indicating a settlement at the furthest point of the village. This was alongside the Wilcot Road and is now in a built-up area that includes the railway station and schools. By 1676 there were about 648 inhabitants of Pewsey. In the 18th century much of the land was enclosed and larger farmhouses built on their farmlands, mainly as a result of this. The small farmhouses close to the village centre were probably no longer farms by this time. From at least the early 18th century bricks were being made here (the industry continued to the start of the 20th century) and this greatly aided new building.
The Phoenix Inn was opened around 1700 and the New Inn, now the Royal Oak, by 1767. By that time there were also three malthouses working. Further expansion came when cottages were built along Easterton Lane in the earlier part of the century and also on waste land at King's Corner in the latter part. It is believed that a white horse was cut on Pewsey Hill in about 1785. It is said that this was done by Robert Pike of Alton Barnes and that it was last scoured in 1789. The scouring was abandoned because of the disruptive nature of the festivities that became associated with it. Remains of the horse noted in the 20th century indicate that it was 43 feet long. A long serving rector, Joseph Townsend (1764-1816), spent much time and energy promoting beneficial works in the parish, and in 1797 was responsible for the building of a red brick, three arched bridge over the river, replacing an inadequate earlier bridge.
It is known that there was a lock-up in the central triangle of the village by the early 19th century. This was probably built in the 18th century and can be seen as an indication of an expanding population. It was demolished in the early 1920s. The building of the Kennet and Avon canal across the parish in 1806-7 had a far-reaching effect. Opened in 1810, with a wharf to the north-west of the village, it provided the means for exporting the agricultural produce of the Vale and allowed materials such as roofing slates to be imported. Another influence of the canal on the landscape was the building of a windmill to provide water for the canal though this was short-lived as it was removed in the 1820s or 1830s.
The village continued to grow (from 1,179 in 1801 to a high point of 2,027 in 1861, after which the population declined until the 1950s) and cottages were built in a settlement called 'Piccadilly', to the west of World's End, early in the century and in Raffin Lane in the middle of the century. The village centre was altered with Phoenix Row, with shops on the ground floor and dwellings above, being built in 1823 and the creation of a market place, at the junction of the three roads, after the granting of a market in 1824. The market was held up to the 1880s, with a weekly corn market at the Phoenix Inn. In 1836 the Pewsey Union Workhouse was built on the north side of Wilcot Road and a police station existed from 1848. A post office was also opened in the village in the first half of the 19th century. The number of public houses was increasing with the King's Arms (now Moonrakers) opening in the High Street in the early 1850s, and the New Inn (now the Greyhound) opening in North Street in the late 1850s. In the late 1860s the Plumber's Arms (now Alfred's) in the High Street and the Crown at the World's End opened.
Pewsey was connected to the railway network by the Berks and Hants Extension Railway in 1862 and a station was built to the north-west of the village in 1863. From 1906 this became part of the London to Exeter main line. In 1863 a cemetery was opened, relieving pressure on local church graveyards, while a gasworks opened in 1865. Around 1870 George Whatley began business as an agricultural engineer, iron and brass founder. In the 20th century the firm expanded, specialising in various forms of mechanical engineering and are still manufacturing in Pewsey as Whatley & Co. Ltd. In 1872 local government in the area passed to the newly-formed Pewsey Rural District Council, which continued until 1974 when its responsibilities were taken over by Kennet District Council. The Ancient Order of Foresters were active in the village, holding an annual fete amongst other activities; and in 1886 they built the Foresters' Hall in the High Street. In 1898-9 a malt house in River Street was converted to a village hall. Named the Bouverie Hall, after Bertrand Pleydell-Bouverie, rector from 1880-1909, it opened in 1899, only closing in 1989 when it was demolished and flats built on the site.
From the 1890s the Pewsey Feast was revived with sports, athletics and cycle racing, providing a popular annual celebration. Another very popular and well-supported event began in 1898 when the first Pewsey Carnival was held to raise money for Savernake Hospital. There had been a fire engine in the village from 1800 at least and in 1902 a new horse-drawn, steam-powered fire engine was purchased and a new building erected in North Street for it. In the early years of the 20th century a waterworks was built in Wilcot Road providing Pewsey with piped water to add to the existing services of gas, fire engine, police and post office; there had also been a bank from the 1860s. Electricity came to the village in 1920 when Pewsey Electric Light Co. converted the Town Mill for electricity generation. From 1921 the street lighting was powered by electricity.

The statue of King Alfred, once Pewsey's royal owner, was erected in 1913 in the middle of the market place, giving a focal point to the village. The role of the workhouse changed in 1915 when Wiltshire County Council used it to house mentally defective patients that were in their care. New buildings were erected in the 1930s, an industrial colony was formed in 1932 and by 1938 there were about 500 patients. Responsibility was transferred to the National Council for Mental Health in 1946 and it became Pewsey Mental Hospital, closing in 1995.
From the 1920s a monthly livestock market was held, ensuring that Pewsey remained central to the local agricultural area, with over 25 shops and many businesses and craftsmen providing goods for the area. Council houses were first built in 1926-7, when 36 were erected in The Crescent, and more followed in the 1930s. A new white horse was cut in 1937, to the left of the site of the old horse, to commemorate the coronation of George VI. It was designed by George Marples and cut by volunteers from Pewsey Fire Brigade in late April. It measures 66 feet long by 45 feet high. During the Second World War a telephone exchange was built on the west side of North Street in 1941, while a British Legion Club opened in 1944. After the war more than 100 council houses were built between 1945 and 1954. From 1951 the land between the Rectory and Easterton Lane, which had been used as a cricket ground, became the village playing field and is now home to Pewsey Vale Football Club.
The second half of the 20th century has seen many more houses and facilities in Pewsey. A Scout Hall opened in 1953; a new Police Station and two police houses were built in 1959, when a branch of the County Library also opened in a shop in the High Street. A new fire station was built in 1963, and secondary modern school in 1956; a swimming pool and sports hall were built alongside this in 1970 by Wiltshire County Council as a shared public and school facility. A new primary school was built on the other side of the school in 1986. In the late 1960s private houses were built in Astley Close, while in the early 1970s about 70 houses and bungalows were built in Swan Meadow. Other small private estates were built in the late 1970s and early 1980s, and the Fordbrook Industrial Estate, to the east of the Marlborough Road, was created in the early 1980s. A boost to tourism was provided by the start of the Kennet and Avon Canal restoration in the 1970s. In 1980 the area that is now Jones's Mill Nature Reserve was given to Wiltshire Wildlife Trust by Mrs Vera Jeans. It is unique among Wiltshire nature reserves as it has a fenland habitat.
Pewsey increased substantially in size in the late 20th century when around 200 houses were built to the west of Hollybush Lane in the 1980s and early 1990s, plus houses in Goddard Road in 1990. The population rose from 2,579 in 1981, to 2,831 in 1991, to 3,237 in 2001. Around 1991 the Salisbury Road Business Park opened. At the start of the 21st century Pewsey is a thriving busy community that has the feel of a small town. There are 29 shops, more than in 1920, and over 100 businesses here altogether.