The chapel of St Eligius, also recorded as St Eloi, once stood within the precinct of St John's Priory and Hospital, a medieval complex that was, by 1540, being methodically dismantled and sold off. The stones, tiles, timber, glass, and iron of the main church were disposed of by William Brabazon, under-treasurer of Ireland, to unnamed buyers for unrecorded sums. It is the kind of erasure that leaves historians working from the edges inward, reconstructing a place from the bureaucratic language of dissolution rather than from any physical trace.

St Eligius was a seventh-century Frankish bishop and the patron saint of metalworkers and smiths, which may or may not explain the dedication of a chapel within a hospital precinct, though no source makes the connection explicit. What the records do show is the scale of what existed here before the Dissolution of the Monasteries. A 1609 grant to Thomas Luttrell describes two-thirds of the site and includes, among other details, a house that had been the chapel of St Eligius, a cemetery, a house containing fifty cells for the sick, a kitchen, a bawn (an enclosed courtyard, typically walled), an orchard, a garden, three water-mills, and a watercourse. The whole property had been divided into three parts for administrative purposes. By that point, the chapel itself had already passed through at least one set of hands; a 1540 survey recorded it as a house occupied by one Edmund Redman. A nearby chapel of St Margaret was noted as unoccupied and worth nothing, for want of a tenant and of repairs.

Thomas Street is a busy thoroughfare today, part of the old medieval axis running west from the city centre, and the Augustinian friary of St John occupies a portion of what was once this much larger complex. The chapel of St Eligius has not been identified within the archaeological record, according to research compiled by Caimin O'Brien and uploaded to the national monuments database in June 2023, citing Clarke 2002. There is nothing to mark the spot, no plaque or outline. What a visitor encounters instead is the layered ordinariness of a city street that has absorbed, and largely forgotten, a medieval hospital precinct of considerable size.