The Church of San Francesco Grande (in Italian: Chiesa di San Francesco Grande) was an ancient church in Milan built in the 4th century and demolished in 1806. It was originally called Basilica di San Nabore after the saint whose remains it houses, but from the 13th century onwards, as the adjoining Franciscan monastery took possession of the monument, it took its new name from Francis of Assisi, founder of the order.

Before the end of the 17th century, the church adopted a rectangular plan. At first, in the part corresponding to the Basilica of Saint Nero, it had a mixture of Lombard Romanesque and Gothic architecture, to which was added a larger part due to the Franciscans. Later, the church continued to grow with the creation of numerous chapels by wealthy donors, who in exchange obtained the right to be buried in sepulchres created by renowned artists. After a first destruction at the end of the 17th century and a reconstruction some ten years later, in 1697, the architectural style of the church became baroque, but its plan remained very close to that of the original building, although it lost ground area.

The church of San Francesco Grande is known for having housed many works by renowned artists such as Bernardino Zenale and Bramante. The most famous work is Leonardo da Vinci's Virgin of the Rocks, which forms the central panel of an altarpiece in a chapel dedicated to the Immaculate Conception.

The building was decommissioned by decision of the Cisalpine Republic in 1798, and was definitively destroyed due to its dilapidation in 1806. Until then, it was the second largest church in the city, after the Cathedral of the Nativity of the Blessed Virgin - that is, the Duomo of Milan.

Location At the time of its destruction in 1806, the church of San Francesco Grande was located within the walls of the city of Milan in Piazza San Ambrose, named after the basilica that borders it.

The present-day Nirone and Santa Valeria streets ran alongside it. In its place, the Garibaldi police barracks now stand.

Church history The history of the church of San Francesco Grande can be described in three main phases between its creation in the first centuries of the Christian era and its destruction in 1806. This history benefits from the archaeological research carried out during several excavation campaigns: a first one in 1939-1940 under the management of Aristide Calderini, then a second one in two phases conducted in 2006-2008 and a third one in 2011–2012 on the occasion of the creation of a car park on the Place Saint Ambrose.

The early centuries of Christianity In ancient times, the site to be occupied by the church of San Francesco Grande was located outside the city walls, a short distance from a gateway to the circus area and the imperial palace.

From the 1st century of the Christian era onwards, this place was part of a vast space that developed as a necropolis made up of several funerary nuclei that were still commonly used until the 3rd century of the Common Era and then more sporadically afterwards. These nuclei are organised around dwellings serving as churches, each with its own cemetery. The complex thus houses the remains of ancient Christian martyrs, constituting the first Christian cemetery in Milan. Saint Ambrose called it the "Cemetery of the Saints" (in Italian: Cimiterio de' santi) or the "Cemetery of the Martyrs" (in Latin: ad martyres) in his memoirs. Excavations show that, despite the construction of churches, the area was used as a burial ground at a later date, with tombs dating from the 5th century.

Amongst these houses, there is in particular that of Filippo de 'Oldani, a Roman consul of the time of Nero who secretly converted to Christianity and buried the remains of St. Gervais and St. Protais here. This is where the church was built. During this time, what is now the primitive church is called, according to hagiographic writings, "Polyandrion Caius et Filippo" (in Latin: Polyandrion Caij et Philippi) from the names of Filippo and Saint Caius, the third bishop of Milan.

In the second century, it was consecrated as a basilica by the bishop of Milan, Saint Castriziano. Then, in the following century, the remains of St. Nabor and St. Felix, who died during the reign of the co-emperor Maximian Hercules, were transferred there from Lodi by Bishop Materne of Milan (episcopate after 314 and before 342).Bishop Materne of Milan also buried St. Victor in the nearby "domus Aurelia". According to the Milanese corpus studied by the researcher Elisabeth Paoli, Materne was himself buried ad sanctum naborem and was thus one of the saints whose body was buried in the church of San Francesco Grande In fact, it is called the "Naborian Basilica" or "Basilica of Saint Nabore" ("San Nabore" in Italian). The transfer is the occasion of festivities that take place in the presence of one of the reigning co-emperors of the Tetrarchy.

All these saints were buried there before being transferred in June 386 by Saint Ambrose to the basilica he founded on the site where Saint Victor had been buried, in the "house of Fausta", named after the daughter of Filippo.

The building of the first real church in place of the domus Philippi is difficult to date, but an inscription on its walls several centuries later assures that it took place at the beginning of the tenth century."The basilica dates back to the year 900 of the Christian era [...]. ("La basilica risale all' anno XC dell'éra cristiana [...].") The Italian priest and historian Paolo Rota (1832 - 1911), however, dates it slightly earlier, to the 7th century.

From the arrival of the Franciscan friars to the first destruction

In the 13th century, the Franciscans - whose order had just been created - settled in Milan. In 1222, they obtained a plot of land behind the Basilica of San Nabore, on which they built a convent and, in 1233, a chapel that they attached to the apse. In 1256, by papal bull of Alexander IV, they received permission to build a church dedicated to the founder of the order, Saint Francis of Assisi. On 14 March 1263 the Pope allowed them to take possession of the church of San Nabore. They then restructured the two buildings to form a single one and named it the "Church of Saint Francis". The first occurrence of this name dates back to 1387 in a calendar of the order, thus confirming the fusion of the basilica and the chapel. The promoters of the construction soon received rich donations from the faithful, who in exchange obtained the right to make it their burial place.

In 1272 a bell tower was erected, but in 1551 it was lowered by a third of its height by the city governor - along with all the city's tallest bell towers - to prevent it from providing a sightline on the newly created city walls. This reduction corresponds to "40 fathoms" or 24 metres, which suggests that it was originally over 70 metres high. Finally, the church was extended and modified between 1570 and 1571.

The chapel and the brotherhood of the Immaculate Conception

In 1475, Father Master Stefano da Oleggio proposed the creation of a chapel dedicated to the Virgin Mary and in particular to the Immaculate Conception. This was taken from a plot of land called "Filippo's garden" (in Italian: orto di Filippo), located close to the atrium, against the chapel of St. John the Evangelist, going towards Via Santa Valeria and Via San Ambrogio. The masonry work was completed in May 1479. The chapel was the last to be built within the church. To get an idea of this, the researchers suggest using the appearance of contemporary chapels built in other churches, such as the Brivio chapel built in 1484 in the Basilica of Sant'Eustorgio: it has a circular, kiosk-like shape. On the occasion of this creation, a secular brotherhood was founded: the Brotherhood of the Immaculate Conception. It is an assembly composed of members of the local aristocracy: the Terzago, Pietrasanta, Orrigoni, Mantegazza, Scanzi and Legnani families are represented, but also the Cotio, Casati and Pozzobonelli families. In fact, the brotherhood is richly endowed.

The object of this brotherhood was new: to promote and defend the dogma of the Immaculate Conception, which was still very much debated since it had only been accepted since 1470 by the papacy, which did not officially proclaim it until 1854; the novelty and precariousness of this dogma thus partly explain the prudence of its members at the time of the reception of The Virgin of the Rocks. An agreement was signed on 1 June 1478 before Antonio di Capitani, notary of the nearby parish of Santa Maria alla Porta, whose services the brotherhood had often used since its creation, defining the links between the newly created brotherhood and the monastery responsible for the church. On this occasion, several prescriptions were issued by those in charge of the church, including one of an absolute nature, which forbids the creation of any opening to the outside of the building.

In May 1480, the work of decorating the chapel was completed, in particular the ceiling, decorated by two artists named Francesco Zavatari and Giorgio della Chiesa: the contractual description of this decoration indicates a representation of God surrounded by a glory of seraphim and four other panels with animals. A few weeks before the end of this work, in April 1480, the woodcarver Giacomo del Maino (before 1469 - 1503 or 1505) was commissioned to build the wooden structure of a large altarpiece, the Altarpiece of the Chapel of the Immaculate Conception. The altarpiece was delivered on 7 August 1482 and still needs to be decorated. In that year, a new prior of the confraternity is appointed, Giannantonio da Sant'Angelo. Painters were commissioned to decorate the structure: the brothers Evangelis and Giovanni Ambrogio de Predis and Leonardo da Vinci. Leonardo da Vinci created the painting of The Virgin of the Rocks, which the chapel would house until the end of the 18th century, Ambrogio painted the Angel musicians on the side panels and Evangelis gilded and decorated the sculpted parts. On the occasion of the creation of this altarpiece, the confraternity showed, despite its relative wealth, a great deal of penny-pinching, as evidenced by the dilatory measures and vague and unfulfilled promises for the remuneration of the participating artists.

The chapel was destroyed in 1576. However, the brotherhood continued its activities: the chapel of Saint John the Baptist, situated to the right of the choir, was allocated to it. This chapel was renamed the Chapel of the Immaculate Conception and the altarpiece was moved there. Around 1635, a testimony indicates that the altarpiece is surrounded by other "small paintings" which are also said to be by Leonardo da Vinci.

Three centuries after its creation, in 1781, the brotherhood was dissolved: its goods were then taken over by the brotherhood of Saint Catherine de la Roue and sold between the end of the 18th century and the beginning of the 19th century, starting with La Vierge aux rochers in 1785.

Final period: from the reconstruction of 1697 to the second destruction