The Basilica di San Lorenzo is one of the largest churches of Florence, Italy, situated at the centre of the main market district of the city, and it is the burial place of all the principal members of the Medici family from Cosimo il Vecchio to Cosimo III. It is one of several churches that claim to be the oldest in Florence, having been consecrated in 393 AD, at which time it stood outside the city walls. For three hundred years it was the city's cathedral, before the official seat of the bishop was transferred to Santa Reparata.

Cosimo di Giovanni de' Medici was an Italian banker and politician who established the Medici family as effective rulers of Florence during much of the Italian Renaissance. His power derived from his wealth as a banker and intermarriage with other rich and powerful families. He was a patron of arts, learning, and architecture. He spent over 600,000 gold florins on art and culture, including Donatello's David, the first freestanding nude male sculpture since antiquity.