Abbey House is now the official residence of the mayors of Winchester and has been in the ownership of the City of Winchester since 1890 when the house and gardens were purchased for public use. The word 'residence' is slightly misleading as the mayors do not live in the house but it is for their use when entertaining. The house and gardens take their name from the site they are on as it was where the former St Mary's Abbey or Nunnaminster stood in the medieval period.
St Mary's Abbey was founded in the 903 AD by King Alfred's widow Ealswith and survived until the dissolution of the monasteries under Henry VIII, finally being surrendered in 1539. The land was in the hands of the crown for only a short period as in 1554 Queen Mary granted the site to the city of Winchester in recompense for the expenses incurred in hosting her marriage to Philip of Spain.
The site remained empty for about 150 years although some of the former monastic buildings may have remained in use for a time, that is until the stone was carried away to repair other buildings around the city such as Winchester College. By 1699 the site was owned by the Pescod family and it is possibly Robert Pescod who built the first house on this site. The house has grown and been much altered since it was first built but It is very possible that the original house, or part of it, still forms the core. The house grew quite quickly and William Godson's 1750 illustrated map of Winchester shows a facade that is more recognisable as the house we see today, at least as viewed from Abbey Gardens.
The house remained in the hands of the Pescods until 1798 when the trustees of George Pescod, who had fallen ill and was declared a 'lunatic', sold the site to the tenant Thomas Weld. Thomas was a prominent Roman Catholic and had two daughters who were Franciscan nuns in Belgium. When his daughters' Abbess, who was also a relative, requested refuge from the turmoil of Revolutionary Europe Thomas offered them Abbey house. Weld had the house altered for the arrival of the nuns and it is possibly that the Gothic castellated facade was added to the Broadway front of the house at this time. The house proved unsuitable as a long term home for the nuns and they moved to Taunton Somerset in 1808 and Thomas sold Abbey House to Robert Jessett.
Abbey House passed through the hands of a number of owners throughout the 19th century and in 1889 was again for sale by auction. Various propositions had been made to develop the site and so the council decided to buy the property mainly to secure the grounds as pleasure gardens for the residents of Winchester. However the council first had to secure a loan of £5000 and the site was not transferred to the city until May 1890. The house was initially partly used as a reference library from 1892 to 1915 and exhibition space for the School of Art but by 1893 it was decided it should be dedicated to the use of the mayor. However from 1894 until 1911 the mayor had to share the house with a collection of sculptures by the sculptor Frederick Thrupp. The collection of sculptures are now to be seen at Torre Abbey, Torquay.