Great Northern War plague outbreak

During the Great Northern War (1700–1721), many towns and areas of the Circum-Baltic and East-Central Europe suffered from a severe outbreak of the plague with a peak from 1708 to 1712. This epidemic was probably part of a pandemic affecting an area from Central Asia to the Mediterranean. Most probably via Constantinople, it spread to Pińczów in southern Poland, where it was first recorded in a Swedish military hospital in 1702. The plague then followed trade, travel and army routes, reached the Baltic coast at Prussia in 1709, affected areas all around the Baltic Sea by 1711 and reached Hamburg by 1712. Therefore, the course of the war and the course of the plague mutually affected each other: while soldiers and refugees were often agents of the plague, the death toll in the military as well as the depopulation of towns and rural areas sometimes severely impacted the ability to resist enemy forces or to supply troops.

This plague was the last to affect the Circum-Baltic, which had experienced several waves of the plague since the Black Death of the 14th century. However, for some areas, it was the most severe. People died within a few days of first showing symptoms. Especially on the eastern coast from Prussia to Estonia, the average death toll for wide areas was up to two thirds or three quarters of the population, and many farms and villages were left completely desolated. It is, however, hard to distinguish between deaths due to a genuine plague infection and deaths due to starvation and other diseases that spread along with the plague. While buboes are recorded among the symptoms, contemporary means of diagnosis were poorly developed, and death records are often unspecific, incomplete or lost. Some towns and areas were affected only for one year, while in other places the plague recurred annually throughout several subsequent years. In some areas, a disproportionally high death toll is recorded for children and women, which may be due to famine and the men being drafted.

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