The Decameron opens with a long realistic prologue describing the 1348 Florentine outbreak of the Black Death. Boccaccio was 35 years old, was personally in Florence through the worst of the epidemic, and lost his father and stepmother to it. His prologue runs to about 6,000 words and is the most detailed eyewitness account of the 14th-century plague produced anywhere in Europe.
One passage in particular concerns mass burial:
Such was the multitude of corpses brought to the churches every day and almost every hour that there was not enough consecrated ground to give them burial, especially since they wanted to deposit each one in the family vault, according to the old custom. So when all the graves were full, huge trenches were dug in the cemeteries of the churches, into which the new arrivals were placed by the hundreds; stowed away layer upon layer like ships’ cargo, each covered with a little earth, until the trench was filled.
The most famous of the Florentine plague pits Boccaccio describes was at the Dominican convent of Santa Maria Novella, on the northwestern edge of the medieval city. He gives the location specifically; he describes the trenches; he records the cargo-stowage layering.
The 2008–2013 excavation
The Italian palaeopathologist Gino Fornaciari of the University of Pisa led a programme of systematic excavation of the substantial Santa Maria Novella subsoil between 2008 and 2013, originally undertaken to investigate the foundations of the basilica complex. The excavation identified a substantial mid-14th-century mass-burial pit beneath the southern cloister, containing the disarticulated remains of approximately 60 individuals in layered burial — adults and children mixed, no grave goods, no individual coffins, the bodies stacked in approximately the cargo-stowage pattern Boccaccio described.
The site dated by radiocarbon to 1340–1380. DNA recovery from the dental pulp of nine individuals identified Yersinia pestis in seven — confirming the burial as a Black Death pit rather than a generic medieval mass grave.
The match between the Decameron’s description and the recovered physical site is the closest archaeological-literary correspondence available for any 14th-century European city. Boccaccio was not exaggerating.
What the Decameron did with it
The framing device of the Decameron is that seven young Florentine women and three young men retreat from the plague-stricken city to a country villa, where they tell each other stories for ten days to distract themselves. The hundred stories that follow — the substance of the Decameron — are mostly comic, romantic, and earthy in tone.
The opening plague-pit prologue is what gives the rest of the book its specific weight. The young storytellers are not on a country holiday; they are refugees from a real city with real mass graves. Every comic seduction and every Florentine satire is being told over the shoulder of the trenches at Santa Maria Novella. The reader of 1353 — every reader of 1353 — would have known someone in a similar pit somewhere.
Boccaccio survived the outbreak. He outlived the Avignon papacy under Clement VI by twenty-two years and died at Certaldo in December 1375, aged 62. The Decameron had become the principal European prose model for vernacular narrative within his lifetime and defined Italian literary tradition for the following two centuries.