HEALTH

The First Named Pandemic

541 CE

History · Middle Ages · Holocene · Meghalayan

In 541 CE plague entered the Roman world through Egyptian ports, opening two centuries of recurring waves. For 1,400 years its cause was conjecture; then DNA drawn from sixth-century teeth named Yersinia pestis. Genomes from Bavaria to Britain have since shown a bacterium already diversifying, on a lineage separate from the Black Death's, and a mass grave in Jordan has now yielded it close to where the outbreak was first recorded.

Why it matters

This is where pathogen palaeogenomics rewrote history: an ancient whodunit closed by sequencing the killer itself, out of its victims' teeth. The Justinianic plague and the Black Death turn out to be separate emergences from rodent reservoirs, eight centuries apart, a warning with a long fuse. How badly 541 broke its world, the end of antiquity for some historians, barely a ripple for others, is a debate the genomes have reopened rather than settled.

Dating & uncertainty

The start of the outbreak in 541 CE is documented by historical sources; the pandemic then returned in waves until about 750. Ancient DNA settled two questions: the cause, Yersinia pestis, and the independence of its lineage, which came out of rodent reservoirs separately from the Black Death's. How many people it killed remains vigorously debated.

Sources

1. Wagner et al. (2014), The Lancet Infectious Diseases · Yersinia pestis and the Plague of Justinian 541-543 AD: a genomic analysisdoi:10.1016/s1473-3099(13)70323-2
2. Keller et al. (2019), PNAS · Ancient Yersinia pestis genomes from across Western Europe reveal early diversification during the First Pandemic (541-750)doi:10.1073/pnas.1820447116
3. Adapa et al. (2025), Genes · Genetic evidence of Yersinia pestis from the First Pandemicdoi:10.3390/genes16080926

Our species’ history as one day

23:53:126 min 47 s before midnight

if the 315,000 years of Homo sapiens were compressed into a single day