The Deadliest Pandemic in History
The Black Death was one of the most devastating pandemics in human history. Sweeping through Europe between 1346 and 1353, it killed an enormous portion of the population in just a few years. Estimates of the death toll range from 25 million to 50 million people, which may have been as much as half of Europe's population at the time. The disease left a permanent mark on medieval society, reshaping its economy, religion, and worldview. For centuries people did not understand what caused it, but modern science has identified the culprit.
The Bacterium Behind the Plague
The Black Death is now understood to have been caused by a bacterium called Yersinia pestis. This same bacterium causes plague, which can take several forms in the human body, the most famous being bubonic plague. Bubonic plague is named for the painful swollen lymph nodes, called buboes, that appear in victims. The disease earned the name Black Death partly because it could cause darkened skin and sores. Modern genetic analysis of remains from plague cemeteries has confirmed the presence of Yersinia pestis, settling a long scientific debate about what the disease actually was.
How the Disease Spread
The plague spread primarily through fleas that lived on rodents, especially rats. When an infected flea bit a human, it could transmit the bacterium and start an infection. The disease is believed to have originated in Central Asia and then traveled westward along busy trade routes. It reached the Crimea and then entered Europe through Mediterranean ports, often carried by merchant ships. According to historical accounts, the plague famously arrived in Sicily in 1347 aboard ships whose crews were already dead or dying. From there it spread with terrifying speed across the continent.
A World Transformed
The consequences of the Black Death reached far beyond the immediate loss of life. With so many people dead, labor became scarce, which gave surviving workers more bargaining power and helped reshape the medieval economy. The pandemic shook religious faith and triggered waves of fear, and minority groups were often unjustly blamed and persecuted. The Black Death also returned in repeated, smaller waves over the following centuries. Studying it has helped scientists and historians understand how pandemics spread and how societies respond to mass catastrophe.
Source
This article was written using information from Wikipedia.