Brunelleschi, Filippo, or Filippo di Ser Brunellesco (1377–1446), Italian architect and engineer, born in Florence, the son of a notary. He trained as a goldsmith and sculptor, and in 1401 he entered the competition for the bronze baptistery doors, which Ghiberti won. Brunelleschi came to architecture as a builder and construction engineer with an acute sense of practical issues and of the mathematics of natural optics; he was less interested than his successors (e.g. Alberti) in the revival of ancient Roman architecture. In or shortly before 1413, Brunelleschi invented a method of giving a naturalistic impression of depth in flat pictures and made two paintings of city views (the first showed the baptistery and the second the Palazzo Vecchio) to demonstrate how well the method worked; it is not known what the method was. See perspective.

Brunelleschi’s architectural commissions, all in Florence, began in 1418. His early projects, some of which cannot be dated precisely, include a domed chapel in San Jacopo Oltrarno (destroyed 1709), the Barbaradori Chapel in the Church of San Felicità (now known as the Capponi Chapel), the Palazzo di Parte Guelfa (now largely rebuilt), and the Church of San Lorenzo (1421–8). In San Lorenzo Brunelleschi first built what is now known as the Old Sacristy (the New Sacristy, 1523–9, was added by Michelangelo), a cube surmounted by a dome in which ribs radiate from the lantern at the centre; Brunelleschi described this construction, which mimics the effect of canvas pressed over the ribs, as having ‘crests and sails’ (a creste e vele). The church is designed as a basilica, but differs from the basilicas of late antiquity in its use of the proportions 1 : 2 and 1 : 4 throughout the building. In the interior Brunelleschi used ribbons of the grey Macigno stone mined in Fiesole and known as pietre serena to emphasize the architectural lines.

In 1419 Brunelleschi received the commission to design and build the Ospedale (or Spedale) degli Innocenti (constructed 1421–44), which is sometimes said to be the first Renaissance building. The façade of the Ospedale (then a foundling hospital, now a museum) is a loggia consisting on the ground floor of an arcade of thin Corinthian columns (the glazed terracotta roundels depicting babies were later added by Andrea della Robbia); above each semicircular arch is a pedimented window, and every detail honours the canons of mathematical proportion. The design proved to be seminal, and created the definitive form of the Renaissance loggia, which was to be imitated for centuries.

In 1420 Brunelleschi began his greatest work, the dome of Florence Cathedral, which was intended to be built in partnership with Ghiberti (with whom he had won the competition jointly) but in the event became Brunelleschi’s project; the design is in some respects Gothic, but the engineering that enabled Brunelleschi to raise the dome without supports is an imaginative revival of the ancient Roman technique of herringbone brickwork. Construction was completed in 1436, and a second competition was initiated for the construction of the lantern; this time Brunelleschi was the unequivocal winner, but construction of the lantern was delayed until 1446; in the interval Brunelleschi built the niched semicircular tribunes (1438) beneath the drum of the dome.

In 1429 Brunelleschi began to build the Pazzi Chapel in the cloister of the Church of Santa Croce. In the interior Brunelleschi again used pietre serena to emphasize the architectural lines. The façade, which has a blank upper storey with rectangular panels, is so different from Brunelleschi’s other work that it seems possible that his designs were replaced with those of another architect when it was constructed after his death.

In 1433 Brunelleschi started to build the Scolari Oratory in the Convent of Santa Maria degli Angeli, but construction stopped before the building was roofed; a roof was added in 1503, and the building was ‘completed’ in 1934, but only the lower parts of Brunelleschi’s walls survived this restoration. These remnants clearly delineate the ground plan of the church, which was to have been the first centrally planned church of the Renaissance: the centre of the church was an octagon, and from each of the eight sides a chapel projected; externally the church was to have had sixteen sides.

Brunelleschi’s last church, started in 1436, was San Spirito. The church is in some respects a reversion to the geometrical basilican plan of San Lorenzo, but Brunelleschi aspired to create the sense of a central space by constructing an aisle around the whole church; his successors demurred, and the west aisle was never built.

Of attributions to Brunelleschi, the most important is the Palazzo Pitti. The rustication and geometry of the façade make it likely that Brunelleschi was the architect who drew up the initial plans for the central section; construction began in 1435, and the palace was eventually finished in 1570 by Ammanati.