The 17th century church of Sant' Ignazio di Loyola is dedicated to St Ignatius of Loyola (1491-1556), the Spanish soldier turned priest, who was the founder of the Order of Jesus, better known as the Jesuits. The building of Sant' Ignazio di Loyola a Campo Marzio, to give the church its full name, was partly funded by Cardinal Ludovico Ludovisi (1595-1632).
The church was designed by a group of architects chaired by Orazio Grassi (1583-1654), who was a Jesuit priest, mathematician and astronomer. Work began in 1626, four years after the canonisation (March 12th, 1622) of Ignatius di Loyola by the cardinal's uncle, Pope Gregory XV (r. 1621-23). Both cardinal and pope are interred in the church.
While the church was opened for public worship in the Holy Year of 1650, it wasn't actually completed until 1685. The facade sports an inscription in honour of Cardinal Ludovisi: S ⋅ IGNATIO ⋅ SOC ⋅ IESV ⋅ FVNDATORI ⋅ LVD ⋅ CARD ⋅ LVDOVISIVS ⋅ S ⋅ R ⋅ E ⋅ VICE ⋅ CANCELLAR ⋅ A ⋅ DOM ⋅ MDCXXVI (To St Ignatius, founder of the Society of Jesus, Cardinal Ludovico Ludovisi, Vice-Chancellor of the Holy Roman Church, the year of the Lord, 1626).
Inscription to Cardinal Ludovico Ludovisi
There is a longer inscription to Cardinal Ludovisi on the counter-facade. It is flanked by stucco statues of Religion and Glory, the work of Alessandro Algardi (1598-1654). The inscription is crowned with the Ludovisi family's coat of arms. A pair of putti seem to be in the act of adding the cardinal's hat!
Apotheosis of St Ignatius by Andrea Pozzo
The stunning ceiling fresco in the nave (1691-94) is the work of a lay-Jesuit, Andrea Pozzo (1642-1709), who also painted the fake dome.
The real dome was never built; the 'dome' we see is simply a painted image on a flat canvas, 17 metres in diameter. The original canvas was destroyed in a fire at the start of the 19th century and was replaced in 1823 by a faithful copy, the work of Francesco Manno, who had access to Pozzo's original cartoons.
The pendentives were also painted by Pozzo and depict four figures from the Old Testament: Judith, David, Samson and Jael.
The paintings in the apse, of scenes from the life of St Ignatius, are also by Pozzo. The fresco in the vault of the half-dome depicts St Ignatius ministering to the plague-stricken. The altarpiece depicts the divine assurance that the saint received in a vision he had in a chapel at La Storta, which lies a short distance to the north of Rome. Above the altarpiece is an inscription: EGO VOBIS ROMAE PROPITIUS ERO (I will be favourable to you in Rome), the words that Christ spoke to St Ignatius in the vision depicted below.
Chapel of the Annunciation
Pozzo also designed the transept chapels. The matching pair of altars sport monumental barley-sugar columns and large marble bas-reliefs. The relief in the right altar depicts the Glory of St Aloysius Gonzaga and is by the French sculptor Pierre Legros the Younger (1666-1719), while the relief of the Annunciation, in the opposite transept, is the work of the Florentine sculptor Filippo della Valle (1698-1768).