Nearby villages are Aldermaston and Mortimer Common in Berkshire, and Baughurst, Pamber, Heath End, Bramley, and Silchester in Hampshire. It is located in the Borough of Basingstoke and Deane. The population, according to the census of 2001, was 11,651; dropping to 11,473 for the census of 2011.
The origin of the name is uncertain. In old maps and books Tadley can be found spelled as Taddanleage, Tederlei, Titherley, Tudurley, Tadel and Taddeley. As with many other rural British communities, it is assumed that the village began as a clearing in the dense forest which at one time covered the greater part of England. In Old English, Tadde means 'Toad' or 'Frog' and ley being 'a clearing in the woods', so it possibly means "a clearing in the woods with frogs". Most sources, however, say that the name means "woodland clearing of a man called Tada".
In 909, Edward the Elder granted the 'Manor of Overton' to Frithstan, Bishop of Winchester. In the confirmation of this a wood at Tadley is mentioned. The village is mentioned frequently in documents relating to the grant. There was an independent estate in the parish called the 'Manor of Tadley' but later was known as the 'Manor of Withford or Wyford'. In 1166 this property was held by William Hotot. He was succeeded by his son, Robert Hotot in 1205. The first reference to a church at Tadley is in 1286 when Andrew Hotot is recorded as owning the Manor and Church. It could be assumed that a settlement and therefore a church existed at an earlier date in view of the documented references to owners of land at Tadley from 909.
Although the exact location is unknown, it is believed that originally Tadley was a rural agricultural village located near to St. Peter's church. This village flourished until the 17th century. At that time, 12 cottages were pulled down by Henry Ludlow and the villagers scattered. They resettled on the fringe of Pamber Forest and woodland crafts became the main employment. By the 18th century, the centre of the village had moved a couple of miles to the northeast, St Peter's had become isolated from its congregation and in 1888 a new church, St. Saviour's, was built by The Green. Burrell's Farm, a cottage on Main Road, is reputed to have been built in the 15th century and is thought to be the oldest building in Tadley. A congregational chapel was founded in Tadley in 1662; this may be identified with a chapel which was converted into the first village school in 1820. By the beginning of the 20th century, there were many Gypsies or didicoy in Tadley — they had given up their travelling life to marry into non-Gypsy families and become property owners.
Until the 1950s, the parish was still heathland and common land covered in gorse and blackberries, with a few scattered settlements. Bricks used to be made at Tadley Common and the manufacture of besom brooms — the type of broom that witches are traditionally said to carry — was, and still is, another local industry. Tadley considers itself the home of besom broom making; the brooms that are used on the Queen's premises are manufactured in Tadley. Relics of these industries can be seen in the names of houses in the village such as Kiln House and Broom Cottage.
With the advent of World War II an airfield, RAF Aldermaston, was built on the grounds of Aldermaston Court which was located on the northern edge of the village. Numerous barracks, administration buildings and maintenance facilities were located throughout Tadley. Local streets such as Hangar Road bear witness to its former usage.
In recent years Tadley has become a township, with residential estates covering the former heathlands. Development has occurred on either side of the Hampshire/Berkshire border following the growth of the Atomic Weapons Establishment on the old Aldermaston airfield in the 1950s and the designation of Basingstoke as a London overspill town in the 1970s.
Since the opening of AWE in the 1950s many anti-nuclear demonstrations have taken place around the base.