The church was part of the conventual complex founded in 1251 by the Umiliati, who had come to Florence from Lombardy in 1239. Although their Rule had been approved by Pope Honorius III, the Order with its fanatical ideal of poverty was felt to teeter on the edge of heresy. It had been founded as a lay congregation for both men and women devoted to Evangelical perfection and poverty, and to physical labour rather than alms-begging. They produced woollen fabrics, and glass. In their arrival in Florence in 1239, the Umiliati settled first outside the city at San Donato in Polverosa, in the area of present-day Novoli, and then near the chapel of Santa Lucia, whose property included the oratory on the borgo where they built their convent and church ‘ad honorem Sanctorum Omnium (in honour of all the Saints).
Between 1251 and 1260 the complex was completed. The site was especially suitable for the working of wool, because where the Mugnone (a small river) ran into the River Arno, beside the Carraia Gate, a small island was formed near Santa Lucia and Ognissanti, its third side being a canal which drove water-wheels and fulling-mills. To make the most of this source of energy the Umiliati constructed the Santa Rosa weir, as well as an intricate system of canals. The urban surroundings were strongly characterised by this building activity, and by the erection of housing for the wool-workers. Such was the prestige attained by the Umiliati that by the end of the 13th century they, together with the Cistercians of Settimo, were invited by the city government to fill certain positions in the public administration. Rich families living near the church began to present it with some extraordinary works of art.

Around 1310 the high altar was adorned with the celebrated Madonna and Child with angels by Giotto, now in the Uffizi. In the sacristy there are other 14th-century works, including a frescoed Crucifixion by Taddeo Gaddi and a painted Crucifix by a follower of Giotto. In the 15th century both Botticelli, who is buried in the church, and Ghirlandaio worked at Ognissanti.
For the Vespucci, Ghirlandaio’s Last Supper (1480) and its sinopia were frescoed in the convent refectory. Domenico Ghirlandaio painted frescoes of the Madonna of Mercy and the Pietà (1470-72) on the second altar. Between the third and the fourth altar is a fresco of St. Augustine in his study by Botticelli, with its pendant opposite: St. Jerome by Ghirlandaio. Both frescoes (now detached) were painted in 1480. However, during the following century the Umiliati declined in numbers and prestige, until in 1571 at the wishes of Cosimo I de’ Medici they exchanged their convent for that of the Observant Friars Minor.
The Franciscans immediately set about altering the complex of Ognissanti. Two new cloisters were built, and the church was re-consecrated in 1582. It was renamed San Salvatore a Ognissanti (St. Saviour at All Saints), the dedication being that of the Friars Minors’ other church on the Monte alle Croci. In 1571 the Franciscans brought from this other church their most precious relic, which is still to be seen at Ognissanti: the habit worn by St. Francis of Assisi when he received the sacred Stigmata on Mount Verna in 1224. Early in the 17th century the friars had their large cloister frescoed with scenes from the Life of St. Francis by Jacopo Ligozzi, Giovanni da San Giovanni, and others. In these episodes the Saint is presented as an alter Christus, his life paralleling that of his divine Master.

The most radical alterations to the church were made between the 17th and 18th century, when new altars, paintings and sculptures were installed. After the destruction of the old choir, the high altar in pietre dure was made in the early 17th century to a design by Jacopo Ligozzi. On the ceiling Giuseppe Romei painted the Glory of St. Francis (1770).
In 1637 the elegant façade was finished, to a design by Matteo Nigetti (restored in 1872, and crowned with the arms of Florence). Above the doorway was placed the 16th-century glazed terracotta Coronation of the Virgin with Saints, attributed to Benedetto Buglioni.
Ognissanti suffered one suppression in 1810 and then a definitive one in 1866.
The convent became a barracks for the Carabinieri in 1923.
From 1885 the friars regained a tiny portion of their original property in which to continue their conventual life.


THE LAST SUPPER

The large refectory of the church of Ognissanti is located between the first and second cloister of the old convent. The room on the opposite wall gives access to a splendid stone door in pietra serena, with two basins, built in 1480, on each side. The niches are decorated with two frescoes referring to water: Sarah at Jacob's pit and Moses who makes water gush from the rock, two 17th century works by Giuseppe Romei. The central fresco, which entirely Downs the wall (8.10 x 4 m), is the work of Domenico Ghirlandaio (1449-1494), who produced with this work one of the best examples of his art, representing a serene yet dramatic episode of the Last Supper. The apostles are painted in the moment in which Jesus announces that one of them will betray him. Following the requests of the monks who commissioned the painting, Ghirlandaio picked out a large number of apparently decorative details, which are in reality a precise symbolic reference to the drama of the Passion and Redemption of Christ, as for instance the evergreen plants, the flight of quails, the oranges, the cherries, the dove and the peacock. By being a separate fresco, it can be compared to the style of the sinopite on the left wall.