The Black Death’s arrival in Europe in 1347 marked the beginning of one of the deadliest pandemics in human history. Originating in Central Asia, the plague—caused by the bacterium Yersinia pestis—traveled westward via the Silk Road and maritime trade routes. A pivotal moment occurred during the Mongol siege of the Genoese trading port of Kaffa in Crimea. Historical accounts suggest that the Golden Horde, suffering from the disease, catapulted infected corpses over the city walls. While the effectiveness of this early biological warfare is debated, it is certain that Genoese merchant ships fleeing the port carried the infection, along with plague-ridden rats and fleas, into the Mediterranean.
The first major European landfall occurred in October 1347, when twelve "death ships" arrived at the port of Messina in Sicily. The crews were either dead or dying, covered in the horrific black swellings, or "buboes," that gave the disease its name. Despite the local authorities’ attempts to expel the vessels, the contagion had already breached the shore. By late 1347, the plague had reached the key maritime hubs of Genoa and Venice, using these bustling commercial arteries to penetrate the Italian mainland. From these gateways, the disease radiated outward with terrifying speed, fueled by overcrowded urban conditions and a total lack of medical understanding regarding its transmission.
By the end of 1347 and into early 1348, the Black Death had firmly established its foothold, spreading from Italy into France and Spain. The pandemic moved through two primary vectors: the bubonic form, spread by flea bites, and the more lethal pneumonic form, which spread through the air. This dual onslaught decimated populations, killing between 30% and 60% of Europe’s inhabitants within a few years. The suddenness of its arrival and the unprecedented mortality rates transformed the continent, leading to the collapse of the feudal system, widespread social upheaval, and a permanent shift in Europe’s economic and religious landscape.