Population, Food, and Mortality

From 1300 to about 1700, Europe's population bounced along without much net gain. The Black Death of 1347-1351 killed something like a third of Europe and left a deep trough in the population curve; recurring outbreaks of plague and famine kept knocking numbers back down for centuries after. Then, starting in the early 1700s, the line bends upward and keeps climbing. Historians point to three forces working together. New crops and farming methods, like crop rotation and new fodder crops, raised food supply and made famine less routine. Plague itself mostly disappeared from Western Europe after the early 1700s, removing the single biggest killer of adults and children alike. And in some regions people began marrying slightly earlier, which stretched out the childbearing years and raised birth rates.

The real engine of growth was not people suddenly having far more children, it was fewer of those children dying. When infant mortality drops, a bigger share of every year's births survives into childhood, then into working age, then into their own childbearing years. That widens the base of a village's age pyramid and, a generation later, swells the middle too, since those surviving cohorts grow up and have children of their own. Populations get younger on average even as they get bigger, because survival is concentrated at the start of life.

This population surge sits right next to the era's intellectual story. More mouths fed, more hands available, and denser cities gave the commercial and agricultural changes of the century somewhere to go, and growing, healthier populations are part of why Enlightenment-era Europe had the economic and social weight to start questioning old arrangements in church and state.