The Great Fire of London Accidentally Ended the Bubonic Plague

The Great Fire of London burned for four days in September 1666, destroying 13,200 houses and 87 churches, including the original St. Paul's Cathedral. While devastating, the fire had an unexpected benefit: it effectively ended the bubonic plague epidemic that had been ravaging London since 1665. The fire destroyed the overcrowded, unsanitary medieval neighborhoods where rats and fleas (the plague carriers) thrived. When London was rebuilt with wider streets, brick buildings, and better sanitation, the conditions that allowed the plague to spread were eliminated. London never experienced another major plague outbreak after the fire.