Great Plague of London
The last major epidemic of bubonic plague in England killed about 100,000 Londoners
January 01, 1665
Plague Returns to England
The Great Plague of London struck in 1665 and was the last major outbreak of bubonic plague in England. Between 1665 and 1666, the disease killed an estimated 100,000 people — about a quarter of London's population. The plague arrived in the summer months, carried by fleas on rats that thrived in London's crowded, unsanitary streets. The city had no understanding of germ theory; people believed the disease was spread by bad air, known as "miasma."
Life in a City Under Plague
Infected households were marked with a red cross and the words "Lord Have Mercy Upon Us." Infected families were sealed inside their homes — along with healthy family members — for 40 days, a practice that accelerated transmission within households. Plague doctors wore their distinctive beak-shaped masks filled with herbs and spices, believing this would filter out the miasma. Wealthy Londoners, including King Charles II and his court, fled to the countryside. The poor had no such option.
End of the Plague and Its Legacy
The plague faded by 1666, and then the Great Fire of London in September of that year destroyed much of the city, incidentally killing many of the rats and fleas that harbored the disease. The Great Plague was chronicled in detail by diarist Samuel Pepys and later fictionalized by Daniel Defoe in "A Journal of the Plague Year." The outbreak drove important early steps in public health, including record-keeping of deaths and attempts at quarantine — laying groundwork for modern epidemiology. See the cholera pandemic story for the next major epidemic age.