The Great Plague (1665-1666) was a massive outbreak of disease in England that killed 75,000 to 100,000 people, up to a fifth of London's population. The disease was historically identified as bubonic plague, an infection by the bacterium Yersinia pestis, transmitted through a rat vector. The 1665-1666 epidemic was on a far smaller scale than the earlier "Black Death" pandemic, a virulent outbreak of disease in Europe between 1347 and 1353. The Bubonic Plague was only remembered afterwards as the "great" plague because it was one of the last widespread outbreaks in England.
Although the disease causing the epidemic has historically been identified as bubonic plague and its variants, no direct evidence of plague has ever been uncovered. Some modern scholars suggest that the symptoms and incubation period indicate that the causal agent may have been a disease similar to a viral hemorrhagic fever.
Several public health efforts were attempted. Physicians were hired by city officials, and burial details were carefully organized. Authorities ordered fires to be kept burning night and day, in hopes that the air would be cleansed. Substances giving off strong odours, such as pepper, hops or frankincense, were also burned, in an attempt to ward off the infection. London residents were strongly urged to smoke tobacco.
Though concentrated in London, the outbreak affected other areas of the country. Perhaps the most famous example was the village of Eyam in Derbyshire. The plague arrived with a merchant carrying a parcel of cloth sent from London. The villagers imposed a quarantine on themselves to stop the further spread of the disease. Spread of the plague was slowed in surrounding areas, but the cost to the village was the death of around 75% of its inhabitants.
Records state that deaths in London crept up to 1,000 people per week, then 2,000 people per week and, by September 1665, to 7,000 persons per week. By late autumn, the death toll began to slow until, in February 1666, it was considered safe enough for the King and his entourage to return to the city. By this time, however, trade with the European continent had spread this outbreak of plague to France, where it died out the following winter.
Plague cases continued at a modest pace until September 1666. On September 2nd and 3rd, the Great Fire of London destroyed much of the most crowded housing. At about the same time, the plague outbreak tapered off, probably due to most of the susceptible persons having already died. After the fire, London was rebuilt on an urban plan originally drafted by architect Christopher Wren which included widened streets, reduced congestion and basic sewage-drainage systems, under the idea that rats may have caused or spread the plague. Due to the severe fire hazard they cause, thatched roofs were forbidden within the city, and remain forbidden under modern codes. The second rebuilding of Shakespeare's Globe Theatre in 1997-8 required a special permit for it to have thatched roofs.