It was founded in 1415 and stood, until its demolition in the 16th century, on the left (northern) bank of the River Thames within the parish of Isleworth, in the county of Middlesex, on or near the site of the present Georgian mansion of Syon House, today in the London Borough of Hounslow.

[3] When Catherine of Siena's Dialogue of Divine Revelation was translated into English for the abbey, it was given a new title, "The Orchard of Syon," and included a separate prologue written to the nuns.

The derelict palace was unfavoured by Henry IV but his son Henry V (1413–1422) saw its reconstruction as a means of emphasising the dynastic link between his own House of Lancaster and that of Plantagenet, of unquestioned legitimacy, and decided at the same time to found the three monasteries pledged by his father in one great, multi-campus building scheme, known as “The King's Great Work”.

Thus the “Great Work” commenced in the winter of 1413–14, comprising a new Sheen Palace, and nearby the following three monasteries:[5] The first stone of Syon Abbey was laid by King Henry V himself on 22 February 1415, in the presence of Richard Clifford, Bishop of London.

[9] The exact location of this original plot is unknown, but it was certainly in the parish of Twickenham, the most northerly river frontage of which lies directly west across the Thames from Sheen Palace.

[19] The reason for the move was to gain more space, as is made clear from the letters patent: "The said Abbess and Convent had presented their humble petition setting forth that their aforesaid monastery was so small and confined in its dimensions that the numerous persons therein ... were not only incommodiously but dangerously situated...that in consequence thereof the said abbess and convent had chosen out a spot in the neighbourhood of their said priory within the said lordship of Isleworth, more meet healthful and salubrious for them to inhabit.

The letters patent authorising the move, which were ratified by a grant by the king dated 1431, make clear that some of the new buildings had already been started and indeed completed: "The Abbess and convent...had begun and with great cost completed the erection of a certain edifice more spacious and convenient as well for the habitation of themselves as of the said religious brethren, which monastery so built anew and enlarged they have earnestly requested licence of us ...to consecrate and set apart as a habitation for them the said abbess and nuns and men of religion...Know ye we therefore of our pity have...permitted them...to the said mansion so chosen and by the said abbess and convent erected edified built and enlarged as aforesaid...to remove immediateley..."[20]It seems that this building, apparently living quarters or “mansion” must have been started several years before 1431 to have been described as “completed” in the letters of patent issued before 1431 There was however another building, possibly the new Church-building itself, which still had not been completed 11 years later, by 1442, when Henry VI issued further letters patent granting the Abbess and Convent special privileges for the transport of building materials from the king's warren in the royal manor of Sheen across the river to Isleworth: That none of the masons, carpenters and tilers or any of their workmen or any of their materials to be employed towards the construction of the new Monastery of Syon, should be taken away by any his officers against their will.

[21]The new site of the church building itself is now believed, after recent archaeological work, to lie partly underneath and to the east of the present Georgian mansion of Syon House.

Reynolds had facilitated a meeting at Syon between Sir Thomas More, the King's chief opponent in his assumption of Supreme Headship, and Elizabeth Barton, the mystic “Holy Maid of Kent” at which More was fueled with supposed divine revelations further supporting his opposition.

Thomas Cromwell, the King's minister in effecting the Dissolution, had visited Syon in person to obtain expressions of acceptance of supremacy, but seems to have met an antagonistic reception from one of the monks at the front-door grate.

He left two of his agents, Thomas Bedyll and Master Leightone, to obtain the required acceptances from the nuns and monks of the King's new status.

He then resorted to what appears a classic use of blackmail, accusing Whitford of having “used bawdy wordes to diverse ladys at the tymes of thaire confession”, which would bring him “to the greate shame of the world”.

Whitford and Little were also reported, whilst hearing confessions through a hole in the wall, of persons external to the monastery, to have denounced the king's new title as Supreme Governor, and his divorce and remarriage, for which reason it was proposed to Cromwell that the confessional grille be bricked-up.

[27] The community were recalled briefly to Syon following the accession of the Catholic Queen Mary I (1553–1558) in 1553 when the Abbey was reestablished by a charted issued on 1 March 1557 by Cardinal Pole.

1. c. 24) was passed annexing and re-dissolving certain religious houses, including Syon, whereupon the nuns obtained royal licence to leave England, eventually settling in Lisbon, Portugal, where they arrived in 1594,[30] after having experienced many troubles and afflictions in travels through France and Spain.

A large piece of sculptured stonework from the monastery's remains was returned to them ceremoniously by the Duke of Northumberland, owner of Syon House.

[34][35] On 14 February 1547 the coffin of King Henry VIII lay overnight at Syon, en route from Westminster for burial in St George's Chapel, Windsor.

Foundations of the Monastery Church lying to the immediate east of Syon House were partially uncovered in excavations starting in summer 2003, made by Channel 4's Time Team archaeological programme, broadcast on 4 January 2004.

[41] The programme highlighted medieval masonry blocks in the foundation wall of the north Wing as evidence that the west end of the church may have been incorporated into the current house built by Protector Somerset.

[43][44] As of 2020, it has been confirmed that some portions of the abbey remained intact and were used in situ during the construction of Syon House, most notably an undercroft forming part of the cellars of the mansion's westerly wing and two Gothic doorways.

[46] A large proportion of this collection comprises material deposited by the sisters of Syon Abbey between 1990 and the monastery's closure in 2011, including the community's archive,[47] manuscripts[48] and printed books.