The church of Santa Maria della Pace was built at the behest of Pope Sixtus IV (r. 1471-84). Its design has been ascribed, without much evidence, to the Florentine architect Bacio Pontelli (c. 1450-92).
In 1656 the Baroque facade, with its semi-circular porch, was added by Pietro da Cortona (1596-1669), on the orders of Pope Alexander VII (r. 1655-67). The inscription is taken from Psalm 72: 'SVSCIPIANT MONTES PACEM POPVLO ET COLLES IVSTITIAM' (The mountains shall bring peace to the people and the hills justice). The quotation is a reference to the 'montini' (a pyramid of small hills) on the coat of arms of the Chigi family, to which the pope belonged. The facade is crowned with two sets of montini.
The short nave of the church is home to three beautiful chapels. The first chapel to the right is the Cappella Chigi with its famous frescoes by Raphael.
The Cappella Cesi (second chapel to the right) was designed by Antonio da Sangallo the Younger (1484-1556) for Angelo Cesi, a lawyer, who acquired the rights to the chapel in 1515. The ornate marble decoration is the work of Simone Mosca; the statues of St Peter and St Paul, and the reliefs of the Prophetsand Angels, are the work of Vincenzo de' Rossi. Rossi also created the tombs of Angelo Cesi and his wife Francesca Carduli. The frescoes on the exterior of the chapel are by Giovanni Battista di Jacopo,better known as il Rosso Fiorentino (the red Florentine).
The frescoes in the Cappella Ponzetti (first chapel on the left) are by the Sienese painter and architect Baldassare Peruzzi (1481-1536). The altarpiece depicts the donor Cardinal Ferdinando Ponzetti, the Virgin, St Bridget and St Catherine of Alexandria. The two busts to the right of the altarpiece are of Beatrice and Lavinia, two of the cardinal's nieces, who died of the plague in 1505, aged six and eight. Ponzetti was physician to Pope Innocent VIII (r. 1484-92).
The nave opens out into an octagon. The design of the cupola has been ascribed to Antonio da Sangallo the Younger with stuccoes by Pietro da Cortona.
The venerated icon of Our Lady of Peace is enshrined in the high altar, which was installed by Carlo Maderno in 1614. The altar is crowned with allegorical statues of Justice and Peace. An inscription proclaims MATER DEI (Mother of God).