The building is sandwiched between the parish church of St. James and the Oratory of St. Christ, and was built on the ruins of the church cemetery porch. It was built in a few years between late 1699 and 1709 by the confraternity of the “Blessed Souls of Purgatory” founded in 1695. Among the documents of the confraternity there is still the original affiliation to the Roman archconfraternity of “B. Maria del Suffragio,” officiating in the church of S. Maria in via Lata. The construction is similar to that of the adjoining oratory, although it has a smaller extension lengthwise, with a single barrel-vaulted nave. The most characteristic part is the extremely simple exterior façade: it has two entrance halls for functional needs similar to those of the “S. Cristo” revealing instead a different layout similar to that of the neighboring oratory; the second, of enlargement, occurred in the years 1772-1778, by engineer La Marchia, followed by a further arrangement a few decades later. La Marchia’s layout saw the inclusion of wooden furnishings in the Piedmontese Baroque taste, including the pulpit. Among the last interventions in the oratory is the fine marble altar made by sculptor Battista Franco.
