The Black Death and its aftermath
Bubonic plague came to England in the summer of 1348. Popularly known as the Black Death, the disease arrived via a French ship that docked in what is now Weymouth on the south coast. From there, it spread rapidly inland and westwards over the water to Ireland. It was also transmitted across the North Sea to Oslo, courtesy of the regular commercial contacts between south-east England and Norway.
Because medieval records are sketchy, estimates of the death toll vary. But it was enormous by any measure.
Norwegian historian Ole J. Benedictow puts the European mortality rate at 60 percent, which would translate into roughly 50 million dead people. Others think that’s too high and the true number was perhaps half of that. For England, an estimate of 50 percent of the population is often used.
The disease, caused by the bacterium Yersinia pestis, was introduced to Europe by virtue of an infected Mongol army besieging a Genoese trading port in Crimea. When the Genoese escaped, the Black Death sailed with them, disembarking in southern Europe in 1347 and making its way to France the following year. Then it was on to England.