According to the research of Professor Gregory Clark of the University of California, Davis, the level of real wages for laborers in England was nearly the same in 1200 as it was in 1800. Yet, during the period from 1350 to 1550, wages were considerably higher nearly 75 percent higher in 1450, for instance, than they were in 1200. Why were real wages temporarily so high during this period?
The simple answer was the bubonic plague also known as the Black Death that arrived from Asia in 1348 and caused a long decline in total population through the 1450s. With fewer workers, there was less labor supplied to the market. The result was higher real wages, although less total output.
In the era before consistent and rapid technological advance, changes in population was the primary factor controlling living standards. As the economist Thomas Malthus (1766 1834) observed, social maladies such as the Black Death would temporarily raise living standards until higher living standards led to increased population.