The key players in the economic transformation in the nineteenth century, as always, were the people – illiterates and the highly educated, males and females, country folk and urbanites, peasants, workers, entrepreneurs, researchers, inventors, doctors, bankers, and government administrators. Demographic changes are themselves important factors in the complex history of the nineteenth century, for Europe's population, for the first time ever in human history, doubled, tripled, and quadrupled in a single century.

The effect of the demographic revolution, however, was not only a much larger European population, but also significantly lengthened life-spans, a healthier population, and decidedly more modern marriage customs, family structures, and even dietary habits. Residential patterns also changed, as a great part of the population moved to rapidly growing cities. The urban explosion had terribly negative side-effects in the first decades, but conditions then improved; the urban settlements were modernized, with better housing, running water, an electric infrastructure, and public transportation. Although industrialization and urbanization uprooted millions of people and led to social upheaval and deteriorating living conditions, the standard of living began to improve from the mid-nineteenth century on. Income differentials were high and even increased for a while. But practically the entire population ultimately enjoyed a higher standard of living around the turn of the twentieth century, and their lives were significantly transformed for the better.