The Black Death was a devastating bubonic plague pandemic that struck Europe, parts of Asia, and North Africa between 1346 and 1353. It is considered one of the deadliest pandemics in human history, killing an estimated 25 to 50 million people-about 30% to 60% of Europe's population at the time
. The disease was caused by the bacterium Yersinia pestis , which was spread primarily by fleas living on black rats that traveled on trade ships. The plague had two main forms during the pandemic: bubonic plague, characterized by swollen lymph nodes called buboes, and pneumonic plague, which infected the lungs and spread directly between people through airborne droplets. A rarer form, septicemic plague, infected the bloodstream and caused rapid death
. The Black Death likely originated in Central Asia and was introduced into Europe through the port of Kaffa in Crimea in 1347, spreading along trade routes into the Mediterranean, North Africa, and the rest of Europe
. It caused massive social, economic, and religious upheaval, including labor shortages that led to wage increases and social unrest such as the Peasants' Revolt in England
. At the time, medical knowledge was limited; people did not understand the bacterial cause and often attributed the plague to supernatural or miasmatic causes. Treatments were largely ineffective, and many victims died quickly, with mass graves used to bury the dead
. The Black Death was the first major outbreak of the second plague pandemic, with subsequent outbreaks continuing into the 18th century. The pandemic profoundly shaped European history by drastically reducing populations and altering economic and social structures
