The name Steventon is thought to be derived from 'Stiffa's Town,' the prefix being the name of a local farmer. Next to nothing is known of the Saxon village, but just before the Norman Conquest the place was a Royal manor, owned by King Harold Godwinsson. At the time of the Domesday Book (1086) it had, of course, passed to King William. The village had a large population of 38 villeins (tenant farmers), 28 bordars (cottage dwellers), 2 serfs and their families. There was a church (probably wooden) and three mills, later called east, west and middle mills. The whereabouts of only one is known. Bizarrely, though previously assessed at 20 hides, it was now said to cover none. The land was later held from the King by his friend, Robert D'Oyley, and became attached to his 'Honour of Wallingford'.

In 1121, King Henry I gave Steventon to the Priory of St. Mary de Pré in Rouen, a cell of Bec Abbey. Soon afterwards, the Abbot sent a number of monks to establish a priory in Steventon. They built a residence on the site of the National Trust's 'Priory Cottages,' and left two of their number there: a prior and his assistant to run the estate with a host of local helpers. It was never the usual sort of priory with a huge church, cloister and lots of outbuildings with monks milling around all over the place. Despite its official status, it was more of an agricultural grange, providing farm produce for the catholic church, while the monks said their prayers in the parish church across the road. The priory building itself, where the two monks lived, was a typical medieval manor house. The present timber-framed building dates from the early 14th century, at the end of the institution's life. The last prior left in 1379 after years of confiscation due to war with France. The priory lands and buildings were then leased to High De Calveley, a hero of the French wars, who needed a rich estate to supplement the income from his small Cheshire home. He may have instigated the rise of the cloth making trade in Steventon, which made the locals rich enough to build themselves the many substantial medieval cottages that survive today. One row was immortalized in WT Blandford Fletcher's painting of 'Evicted Steventon 1887'.

The monks of Steventon are best-known for having built the famous 'Steventon Causeway,' a ditch-flanked stone-paved path that stretches through the village, way above the level of the road. It is thought to date from the early 13th century and is said to have been constructed so that that, not only the monks, but also the villagers, could keep their feet dry in wet and muddy whether, when travelling to and from the church. It is about a mile long and some people think it may, at one time, have stretched as far as Sutton Courtenay or even Abingdon Abbey. The parish church stands at the far end of the causeway, on the site of the old Saxon building. It has a yew tree in the churchyard that is thought to be some twelve hundred years old! The present building is mostly 14th century. It houses a large collection of very finely carved roof bosses, though uncoloured, and good memorial brasses and ledger stones to the Doe and Wiseman families who were 15th & 16th century lords of the manor. 

The manor was given to the Dean & Chapter of Westminster in 1399 and the Priory building became the manor house. The Abbey was continually loosing and regaining it, but, throughout, leased it first to the Hopkins family and then to the Wisemans. Thomas Smallbone, who had married a Hopkins widow, was so dissatisfied with his new landlords after the Dissolution of the Monasteries that, in 1552, he bribed the Dean of Westminster to try and recover Steventon. When he failed, Thomas sued him for the return if his bribe money! An old manorial custom that survived until 1890, was the sale of the cut grass from the green and the roadside by way of a candle auction. A nail was thrust into a lit candle and bidding continued until the wax had lowered so much that the nail fell out. Such an auction is still held regularly in Aldermaston.

Some of the earliest quakers used to meet in Steventon, but they were not popular with the Church of England. It is recorded that, in October 1660, "a constabIe and others armed with pitchforks, bills, staves and such like weapons, entered a meeting at Steventon in Berkshire, pulled out Thomas Curtis and threw him into a pond, tearing his coat in pieces: With the like barbarity they used several others, sparing neither age nor sex. One of them was trodden on and kept down in the water till some of their own company cried out, you'll drown the man. After which they drove the innocent people along the highway, inhumanly abusing and bemiring them. This abuse was said to be given them at the instigation of a drunken priest, who being told, that his weapons ought to be spiritual, replied that he would fight the Quakers with such weapons as he had."

In the 1830s plans were afoot for the Great Western Railway, between Reading and Bristol, to be laid north of the Berkshire Downs in the Vale of the White Horse. Isambard Kingdom Brunel surveyed the route himself and decided it would run through Steventon. The line was opened in June 1840 and the station built in the village became an important railway hub, half-way between the two metropolises. Brunel built two large houses nearby. The Superintendent's House (now Station House) became the HQ of the GWR for a while. Brunel probably kept a design team there and, in the second half of 1842, the company's board meetings were held in the house. The second building was an hotel (now Brook House) where travellers to and from Oxford could stay. At the time, Steventon was the closest stop to Oxford. Horse-and-Coaches left for the hour-and-a-half ten mile journey to that city eight times a day until the Didcot branch line was opened in 1844.