Will von Behr, MA
A Brief History of San Lorenzo in Florence
What is San Lorenzo?
San Lorenzo is a grand 15th-century church complex designed by some of the leading lights of the Renaissance.

sailko, CC BY-SA 4.0, via Wikimedia Commons
San Lorenzo History
The Basilica of San Lorenzo is most likely the earliest cathedral in Florence, and before the iconic Duomo it was the main religious centre of the Florentine city state. Historical records indicate that the Church of San Lorenzo dates back to as early as AD 393 when it was consecrated by Saint Ambrose of Milan. The façade of the building, for which Michelangelo drew up designs in the 16th century, remains rough and unfinished; however, don’t let this fool you. Inside the church complex are some of the greatest achievements in Italian art and architecture. These include Michelangelo’s Laurentian Library and New Sacristy, as well as Filippo Brunelleschi’s Old Sacristy and artworks by Donatello, Rosso Fiorentino and Fra Filippo Lippi.
Although the site of San Lorenzo was consecrated as early as the 4th century, the historical significance of the building as an example of Renaissance architecture begins in the 15th century. The structure as we now know it was begun by the famous architect Filippo Brunelleschi in 1419. However, owing to issues with funding, and multiple changes of designer and patron, the project dragged out well into the 1490s. Because of this, the resulting layout deviated somewhat from the original plans set out by the master architect. For example, the chapels were supposed to be much bigger, and the columns elevated on plinths. In some ways, though, this deviation can be read as a blessing rather than a curse, because it means that the current design of San Lorenzo charts its history, with many different hands contributing to the final form.
First, there’s the Old Sacristy designed by Brunelleschi. The space is a typical rendition of Renaissance architectural ideals of proportion, geometry and balance. The sculptural scenes that decorate the interior, celebrating the life of Saint John the Evangelist, are must-see works by Donatello. The small dome over the altar also is especially fine, painted bright blue and gold to depict the night sky and constellations as they appeared over the city on the 4th of July 1442.
Then there’s the masterwork by Michelangelo known as the New Sacristy, part of the celebrated Medici Chapels. Florence’s most famous family played an integral part in the history of San Lorenzo, not only because they funded many of the notable features within the church, but also because the site was within their local parish. Michelangelo’s New Sacristy is a testament to their financial and artistic power.
Thirdly, the complex houses the beautiful Biblioteca Laurenziana (or Laurentian Library), designed by Michelangelo in the early 16th century. This consummate example of Mannerist architecture remains in use, currently housing thousands of early manuscripts and printed books. The design of its convex, three-tier staircase is particularly fine. Located here within Florence’s main market district, the entire complex of the basilica is well worth a visit.
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