Created around 1754, Giorgio Massari’s Altar of San Giovanni Nepomuceno provides a harmonious architectural setting for Giambattista Tiepolo’s Vision of Saint John Nepomuk. The altar displays a carefully balanced classical composition, with pairs of Corinthian columns flanking the altarpiece and supporting a projecting entablature surmounted by a curved pediment enriched with a carved shell motif. The pale stone surfaces and restrained ornamentation reinforce the structure’s solemn character, while the altar table, embellished with carved panels and a central cartouche, provides an elegant counterpoint to the architectural framework above. The result is a unified ensemble in which the measured grandeur of the architecture frames and heightens the theatrical intensity of Tiepolo’s painting.

The altar acquired its present setting during the extensive Neoclassical renovation undertaken by architect David Rossi between 1799 and 1804. The project transformed the interior of the medieval church, replacing its irregular colonnades with a more orderly sequence of Ionic columns and enlarging the main chapel through the addition of an apse. Massari’s altar and Tiepolo’s painting were relocated to a newly constructed, barrel-vaulted recess, where the stone structure was incorporated into the architectural language of the renovated church.

Rossi’s intervention also changed the way visitors encountered the ensemble. As part of the reorganization of the church’s southern side, the large late-Gothic portal was dismantled and moved from its original position to the center of the side wall. This new arrangement established a direct visual relationship between the entrance and Massari’s altar, bringing Tiepolo’s painting immediately into view upon entering the church. The result was a carefully framed architectural setting in which the 18th-century altar became an integral part of the renewed interior, connecting Massari’s design with Rossi’s broader transformation of San Polo.

The architectural ensemble shows signs of deterioration, including accumulated dirt, moisture staining, and alterations resulting from earlier repairs. Deposits of dust and grime are particularly pronounced in the upper sections of the structure, giving the stonework a darkened appearance that obscures its architectural details and decorative elements. Prolonged exposure to moisture has also weakened certain areas, particularly around the bases of the columns, causing surface erosion and localized losses of material.

The proposed conservation treatment will include careful cleaning of the marble and stone surfaces, the removal of harmful salt deposits, and the consolidation of weakened areas. Previous repairs will be assessed and treated where necessary, while losses and open joints will be addressed using compatible conservation materials. These interventions aim to recover the clarity and balance of the altar’s architectural design, stabilize its deteriorated elements, and ensure its long-term preservation.

Giorgio Massari (1687 – 1766)
Altar of San Giovanni Nepomuceno
ca. 1754, marble and stone
830 x 520 cm

Bisson, Massimo. L’architettura della chiesa di San Polo tra Medioevo e Settecento: strasformazioni, “cancellazioni”, sopravvivenze. In Matino, Gabriele and Dorit Raines (eds.). La chiesa e la parrocchia di San Polo. Spazio religioso e spazio pubblico. Rome: Viella, 2021, pp. 125-144. Link to the Article

Fassl, Johanna. Sacred Eloquence. Giambattista Tiepolo and the Rhetoric of the Altarpiece. Bern etc.: Peter Lang, 2010, pp. 277-291