Population loss due to plague in select cities in the Great Northern War 1709-1713

The Great Northern War was a major conflict in Europe at the beginning of the eighteenth century, and saw Russia defeat Sweden to become the strongest power in the Baltic region, and emerge as one of the continent's most powerful empires. One of the often-overlooked components of the war was a plague outbreak that killed tens of thousands of people during the war, and also impacted each army's ability to reinforce their numbers or to hold positions in infected towns and villages. Some cities are estimated to have lost more than half of their population during this epidemic, particularly along the coast between modern-day Poland and Estonia; the outbreaks experienced along the Baltic coast during the Great Northern War were sometimes larger and deadlier than the outbreaks experienced during the Black Death. While it is impossible for modern historians to differentiate the extent to which the deaths were due to plague, famine or other diseases during the war, it is generally agreed that bubonic plague was the chief culprit among these causes. This outbreak is just one example of many, which highlights how war has facilitated the outbreak of various epidemics throughout history, other examples include the Great Smallpox Pandemic of the 1870s, or the Spanish Flu outbreak of 1918.