Europeans in the fourteenth century were looking at the world in a new way, seeing far-off places as desirable, worth finding out about, maybe worth acquiring. Yet before Europeans really got out and started taking over that world, there had to be enough personal wealth back home to make a decent-sized market for foreign luxuries. Oddly, it took a horrible disease and mass-scale death for that market to find a foothold.
The Black Death (also called the Black Plague), a devastating epidemic of bubonic plague and its variants, probably started in the foothills of Asia's Himalayan mountain range. But in the fourteenth century something happened to make disease spread — perhaps the rise of trade. The disease lived in fleas carried by rats. Where people go, especially people carrying food, so go rats and their parasites.
When a rat died, the fleas jumped to another rat. When no other rat was handy, the fleas tried less desirable hosts. When those hosts were human, the people got terribly sick and most of them died quickly. An even more deadly version of the disease, pneumonic plague, spread through the air from person to person.
The blackish bruises that appeared beneath their skin were called buboes. That's where the name bubonic plague comes from. (Think of that next time you hear a child call a bruise a "boo-boo.")
Killing relentlessly
In 1333, the plague killed thousands of Chinese. The disease spread west. By 1347, it reached Constantinople, where it was called "The Great Dying," and it continued rapidly west through the Balkans, Italy, France, and Spain. Then year by year, the disease advanced northward. Within a few years the Black Death reached Russia, Scandinavia, and beyond, following the Viking trade routes to Iceland and completely wiping out Norse settlements in Greenland.
As many as 25,000,000 people died in Europe. Maybe a third of the people in England fell. Periodic outbreaks followed for centuries after, but the Black Death had an impact even beyond the horror and sorrow and the morbid fascination it inspired. (Many examples of art from this time focus on disease and death.)
The children's rhyme "Ring Around the Rosie" is much older, and much more morbid, than many modern parents realize. It goes back to plague times, when the "rosie" was a rash that appeared as victims first came down with the disease. "Pocket full of posies" refers to the erroneous belief that flower petals were a defense against sickness. The posies did sometimes help with the overwhelming smell of death. "Ashes, ashes," is from the funereal "ashes to ashes, dust to dust." And the final line, "all fall down" originally carried the understanding that few, if any, would get back up again.
Doing the math: Fewer people equals more wealth
Plague so drastically reduced Europe's population that a smaller labor pool changed the economy. Ironically, this improved many Europeans' lives — creating disposable income, which spurred a demand for eastern luxuries and even eastern ideas. (The intellectual and cultural result of this reduction in population and eastward focus was called the Renaissance.)
With so many dead, fewer people were left to work the land. A few workers had the spunk to stand up to the nobles and landowners and point out that they weren't about to give more work for the same money — not when the supply of workers had become smaller and thus more valuable. The most famous of these uprisings was led by Wat Tyler, an English rabble-rouser who got himself killed for his trouble in 1381.
Post-plague economics forced some large landholders to split their estates into smaller plots. Instead of remaining tenants who turned over the bulk of their crop to the landlord, some laborers actually began earning pay for their work.
Though there were fewer people overall, more people had land, income, and the potential to buy goods. This stimulated a rise in merchants, craftspeople, and skilled traders who could supply goods. Up until that time, you were either rich or poor, usually poor. Now there was a middle class.