The earliest known home of the King's Inns was established within the former precinct of St Saviour's Priory, a Dominican foundation whose buildings were repurposed in the upheaval following the dissolution of the monasteries in Ireland. According to historian Clarke, the Inn was already in occupation there by 1539, making it one of the earlier institutional adaptations of a suppressed religious house in the city.

St Saviour's Priory, recorded in the archaeological inventory as DU018-020050, had been a significant Dominican presence in Dublin before the Reformation swept away such foundations. After its dissolution, the site did not sit idle for long. The complex, which retained its gardens and orchards within enclosing stone walls, passed through the hands of the Crown before being granted in 1578 to the 10th Earl of Ormond. That grant, of a walled precinct still containing its horticultural grounds, gives some sense of how substantial the original priory complex must have been, and how desirable such enclosed urban landholdings were in sixteenth-century Dublin. The period between 1539 and 1578 represents the window during which the lawyers occupied the old priory buildings, an arrangement not uncommon in post-dissolution Ireland, where legal and administrative bodies frequently moved into the vacated shells of religious houses.

The original site associated with St Saviour's Priory lies in the north inner city, in the area around what is now Dominick Street and the surrounding streets, though little of the medieval fabric survives above ground. Visitors interested in the layered history of this part of Dublin will find the neighbourhood rewards slow walking and some advance reading. The physical traces of the priory and its post-dissolution life as a legal inn are largely gone, absorbed into centuries of subsequent building, but the historical record preserved in Clarke's work gives enough detail to locate the general area and appreciate what once stood there. For those following the documentary trail rather than standing stones, the relevant archaeological record is catalogued under the Sites and Monuments Record reference DU018-020050.