Basilica of Santa Maria del Popolo Historical Timeline

A demon-haunted walnut tree, a Renaissance rebuild, and then a century in which half of Rome's greatest artists worked on one small church.

Chronology

1. after 68 CE — in the legend attached to the site, after his suicide Nero is buried in the mausoleum of his paternal family, and on its ruins grows a huge walnut tree that was "so tall and sublime that no other plant exceeded it in any ways". The tree becomes the haunt for a multitude of vicious demons harassing travellers. Structural impact: none yet — but it is why a church was put precisely here. What you see today: the site itself, at the old north gate of the city.
2. 1099 — on the Thursday after the Third Sunday of Lent, the Pope organises the entire clergy and populace of Rome in one impressive procession and performs an exorcism; Paschal II places the first stone of an altar at the former site of the walnut tree. Structural impact: the first church on the spot. What you see today: nothing of it, but the dedication and the site.
3. 1472–1477 — soon after its transfer to the prestigious Lombard Congregation, the church is reconstructed on the orders of Pope Sixtus IV. The façade is built in early Renaissance style in the same decade. Structural impact: the basilica as a Renaissance building, an early and excellent example of the style in Rome. What you see today: the shell, the plan and the façade.
4. late 15th–early 16th century — Andrea Bregno builds the chapel that Turismo Roma calls the Cappella del Presepio, decorated with magnificent frescoes attributed to Pinturicchio and his workshop; the main altarpiece, The Adoration of the Child with St Jerome, is an exquisite autograph work by Pinturicchio himself. Structural impact: the first of the great private chapels. What you see today: the frescoes and the altarpiece.
5. 1505–1507 — Andrea Sansovino creates two monumental tombs, for Cardinal Ascanio Sforza (died 1505) and Cardinal Girolamo Basso della Rovere (died 1507), the favourite cousin of the pope. Structural impact: the choir becomes a mausoleum as well as a sanctuary. What you see today: both tombs, flanking the choir.
6. 1507 — Julius II grants assent to the wealthy Sienese banker Agostino Chigi to build a mausoleum replacing the second side chapel on the left. Structural impact: the Chigi Chapel begins. What you see today: the chapel, second on the left.
7. early 16th century — the Julius II choir is built in High Renaissance style, decorated with the frescoes of Pinturicchio on the sail vault and the stained glass windows of Guillaume de Marcillat — the oldest stained glass window in Rome is here. Structural impact: the church acquires a monumental choir. What you see today: the vault frescoes and the glass.
8. 1513–1516 — the Chigi Chapel is realised to Raphael's design for Agostino Chigi and partially completed by 1516. The dome of the centralised octagonal chapel carries Raphael's mosaics, the Creation of the World. Structural impact: a centrally planned chapel by the leading painter of the age. What you see today: the architecture and the dome mosaics.
9. 8 July 1600 — Monsignor Tiberio Cerasi purchases the patronage right of the old Foscari Chapel. The new Cerasi Chapel is designed by Carlo Maderno between 1600 and 1601. Structural impact: the chapel that will hold the Caravaggios. What you see today: Maderno's chapel, left of the high altar.
10. around 1601 — the Cerasi Chapel is decorated with two large Baroque canvases by Caravaggio: the Conversion of Saint Paul and the Crucifixion of Saint Peter. Structural impact: none to the fabric; everything to the reason people come. What you see today: both paintings, in the chapel they were painted for.
11. 1652–1656 — Fabio Chigi becomes cardinal priest of the church in 1652 and immediately begins the reconstruction of the neglected family chapel, which is embellished by Gian Lorenzo Bernini. His additions include the sculptures of Habakkuk and the Angel and Daniel and the Lion. Structural impact: Raphael's chapel completed, 140 years on. What you see today: the chapel as both men left it.
12. March 1658 — Alexander VII — Fabio Chigi, now pope — inspects the work in the company of the architect. This proves to be a significant rebuilding that alters the character of the quattrocento basilica: the façade is changed, larger windows are opened in the nave, and statues, frescoes and stucco decorations are added, with a new main altar erected. Structural impact: a Renaissance church given a Baroque skin. What you see today: essentially this building.
13. today — a parish basilica run by the Augustinian order, with no published hours and no admission charge. Structural impact: none. What you see today: one of the densest collections of first-rank art in any church in Rome, free at the door.

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