The church of Sant'Ignazio di Loyola is the second Jesuit church in Rome and is a splendid Baroque building in the square of the same name. It is dedicated to St. Ignatius, founder of the Jesuit Order. It was built in 1626 by Jesuit Orazio Grassi and commissioned by Cardinal Ludovico Ludovisi.
The Piazza Sant'Ignazio in front of the church of St. Ignazio di Loyola is a theater set of buildings laid out by Raguzzini in a late baroque/early rococo style. Inside the church—designed by the Jesuit mathematician Orazio Grassi, who modeled it after plans by Carlo Maderno—the sense of theater continues. First of all, attention must be paid to the ceiling of the nave overhead. It is breathtakingly, dizzyingly, swimmingly decorated in a riotous, colroful, and amazingly masterful tromp l’oeil 1685 fresco depciting St. Ignatius and his Works by perhaps the greatest baroque master of perspective there ever was, Andrea Pozzo (who was himself a lay brother of the Jesuit order).