Upon entering the small Piazza del Gesù (literally, “The Square of Jesus”) in the heart of the old city, the spectacular façade of the Church of the Jesuits grasps the viewer’s attention. It outstands even the stunning Zeuli and Calò Carducci buildings located in the adjacent street. The church was built over the ruins of St. Catherine's Church, and reconstruction began on May 23rd, 1589, the day the Bishop Fortiguerra of Bitonto blessed the foundation stone. It was erected in the southern part of the city that had of late been encompassed into the city walls, and soon became the centre of great political dispute. The nearby Piazza Maggiore (today, Piazza Mercantile) had been recently chosen to house the Palazzo del Sedile (Town Hall). The Jesuits had arrived in Bari in 1583 and had carefully selected the construction site for their church, designed to overshadow the grandeur of the main façade of the nearby St. Theresa Monastery. Chronicles of the time report that the arrival of the Jesuits in Bari brought great changes to the way the people practiced the religion; they were not even accustomed to the ritual of the communion. In the church, the Jesuits promoted a rigid and dogmatic religion, while, in the annexed college, they founded a school that taught Latin, Ancient Greek, Rhetoric and Philosophy. At first, neither the Universitas (Town Council) nor the secular clergy were in favour of the arrival of the Jesuits in Bari because they would have been a heavy economic burden to the already impoverished finances of the city. As a result, the construction project was postponed to 1589 when the Jesuits received the aforementioned church of St. Catherine (later demolished) as a donation from the Archbishop A. Puteo, as well as 1000 ducats from the Universitas for the building’s basic needs.
The structure of the building, albeit impressive, appears rather simple compared to the splendour of the Jesuit churches in Rome or Naples; this is intended to highlight the aspect of it being a place of prayer.
The Baroque façade has a dramatic and solemn appearance. It is divided into two sections by a projecting cornice. Despite its grandeur, the façade is softened by the gentle dynamism created by the six large pilasters and the richly decorated scallop-shell applique with curls and scrolls situated above the only entrance, as well as by the simpler mixtilinear window in the central upper section. The elegant contrast between the dark local tuff and the light-coloured limestone of the portal and wainscot defines the harmony of the visual impact. On the inside of the church, a wooden choir surmounts the entrance portal. The interior space consists of a single rectangular nave that ends with an apse covered by a barrel vault with lunettes along its length. High pilasters decorated with Corinthian capitals punctuate the lateral walls and delimit the spaces, in the central part, which house the paintings of St. Ignatius of Loyola, on the left, and St. Francis Xavier, on the right, founders of the Jesuit Order in 1534. Polychromatic marble altars embellish the décor of the side chapels. Half way down the nave, on the right, there is an elegant pulpit with wooden railings used by the Jesuits. The Carrara marble altar stands on a raised four-step presbytery, and is enclosed by a marble balustrade.