Final answer:
The Black Death was a devastating pandemic caused by Yersinia pestis, leading to massive population loss and socio-economic changes in 14th century Europe, Asia, and Africa. Its impact was exacerbated by prior conditions like the Great Famine, and it significantly weakened the feudal system.
Step-by-step explanation:
The Black Death, one of the deadliest pandemics in human history, struck Europe, Asia, and Africa in the mid-14th century. Originating in Asia, probably in China, it reached Europe via the Silk Road and other trade routes, with the bacterium Yersinia pestis as the causative agent. This pathogen was carried by rat fleas living on black rats, a common pest aboard trading ships.
Europe, already reeling from the effects of the Great Famine caused by bad weather and resulting in widespread crop failures and malnutrition, was particularly hard-hit. The famine had weakened the population's immune systems, which made the populace more susceptible to the plague when it arrived. The Black Death led to the deaths of tens of millions in Europe alone, with an estimated 40% to 60% of its population perishing. The mortality rate for those infected was extremely high, with the pneumonic form almost always resulting in death within twenty-four hours.
In addition to the staggering loss of life, the pandemic had significant socio-economic impacts. It led to the end of the feudal system due to the radical decrease in the labor force, and it also initiated or accelerated other socio-economic changes in Western Eurasia and Northern Africa. Understanding the historical context of the Black Death continues to be important, especially as Yersinia pestis still exists today, although modern antibiotics have drastically lowered mortality rates.