The Basilica of St Gregory the Great at Downside, commonly known as Downside Abbey, is a Benedictine monastery in England and the senior community of the English Benedictine Congregation. Its main apostolate is the Downside School, for the education of children aged eleven to eighteen.
Both the abbey and the school are located at Stratton-on-the-Fosse between Westfield and Shepton Mallet in Somerset, South West England. In 2017, the abbey was home to fourteen monks. From 1 September 2018 Rev Dom Nicholas Wetz from the Belmont Abbey serves as its Prior Administrator.
Downside Abbey has been designated by English Heritage as a Grade I listed building.Sir Nikolaus Pevsner described the Abbey as "the most splendid demonstration of the renaissance of Roman Catholicism in England".
The community was founded in 1607 at Douai in Flanders, then part of the Spanish Netherlands, under the patronage of St Gregory the Great (who had sent the monk, St Augustine of Canterbury, as head of a mission to England in 597). The founder was the Welshman St John Roberts, who became the first prior and established the new community with other monks from Britain who had entered various monasteries within the Spanish Benedictine Congregation, notably the principal monastery at Valladolid. In 1611 Dom Philippe de Caverel, abbot of St. Vaast's Abbey at Arras, built and endowed a monastery for the community.