By: Dorsey Armstrong, Ph.D., Purdue University
The Black Death that reared its head on the steppes of Asia in 1346, ravaged port cities, such as Messina, Venice, Genoa, Pisa, Marseille, and the island of Mallorca. It then moved northwest hitting Britain in 1348 and moving north into Scandinavia and striking Sweden in 1349.

Learn more about the epidemiology of plague.
The Black Death’s Entry into Europe
By 1347, the Black Death had moved west and south, striking Crimea and, most importantly, the great city of Constantinople, which was a center of trade and culture and a political and religious capital. After laying waste to some of Europe’s most important port cities, what the great plague scholar Ole Benedictow has called bridgeheads, the Great Mortality began to move overland in a generally northwest direction, but at the same time, it was continuing to move much more rapidly over various waterways.
The Role of Trade Routes in Spreading the Plague in Europe
Understanding how the plague moved through medieval Europe is very crucial to know more about its devastating effects. It was the trade routes, especially the sea routes—that were part of a newly burgeoning and flourishing economy—that helped the plague move so quickly and effect such great devastation. A close observation suggests that if the Black Death arrived in England in 1348, soon all of Britain, including Ireland, which was infected through its various port cities and trade networks, would be overcome. The fact that the Irish city of Dublin and the English city of Bristol were both affected around the same time suggests that Ireland and England were both infected via trade from the continent.
Interestingly, Scotland, which is physically connected to England, does not suffer from the Black Death until 1350. By contrast, Norway, which is separated by a vast expanse of water, gets affected by the plague earlier, in 1349. Sweden, in fact, got infected from Norway. Denmark was infected that same year, but most likely by a separate wave of plague that was coming up from the south. That wave would crash into another current of plague that entered Denmark via trade networks with Norway. In 1352, the plague struck much of Russia, including Novgorod and Moscow. While the distance between the steppes of Asia and Moscow and its environs is quite short, the Black Death nevertheless reached there. It is a clear example of how established trade routes were the means of infection.

Learn more about the Black Death’s ports of entry.
Scandinavia’s Experience with the Plague
It must be noted that different parts of Scandinavia were infected at different times and by different routes. The Scandinavian experience of the plague was marked by a fascinating folktale response in which the Black Death was anthropomorphized variously into an old woman, a pair of children, an old man, and in some cases, it was depicted as frightening animals from hell, such as a three-legged goat with blazing eyes. And these depictions seem to be found nowhere else—they are culturally unique to Norway, Sweden, Denmark, and Finland. Iceland completely escaped the first wave of the Black Death and did not experience it until 1402.
This is a transcript from the video series The Black Death: The World’s Most Devastating Plague. Watch it now on The Great Courses Plus.
Doubt Concerning the Source of the Plague

There was a controversy about whether the Black Death actually afflicted Scandinavia or it was something else. The reason for the doubt concerning the source of the epidemic that struck the north of Europe is that the main carrier of the infected fleas—the black rat, or Rattus rattus—was not commonly found in Northern Europe. In fact, a different species of rat, Rattus norvegicus, was the most populous in the north, and its ancestor and that of Rattus rattus diverged from one another about 1.2 million years ago. Rattus norvegicus, or the Norway rat, do not tend to host the fleas that carry Yersinia pestis. However, as many scholars have simultaneously proven, the fleas that carry the plague can live without a host for anywhere from 30–50 days and were easily transportable in merchant goods like cloth or grain, and thus, the infection could have come into Scandinavia that way.
Identifying the Source of the Infection
Another thing that seems to become clearer is that pneumonic plague could be spread from person to person. It does not necessarily seem to be the case that the bubonic form of the plague needed to also be circulating at the same time. In any event, it was settled that various forms of bubonic plague are what caused most of the high death rate in Scandinavia between 1349 and 1351. The source of the infection has been identified by many sources as a specific ship carrying wool to Norway that departed London in May 1349, probably intending to arrive and unload its cargo in Oslo. Somewhere en route, plague swept through the ship—one of the crew must have been infected but didn’t know it before embarking.
Learn more about the medieval theories about the Black Death.
Common Questions About the Black Death in Scandinavia
It was the trade routes, especially the sea routes—that were part of a newly burgeoning and flourishing economy—that helped the plague move so quickly and effect such great devastation in Europe.
The reason for doubting the source of the epidemic that struck the north of Europe is that the main carrier of the infected fleas—the black rat, or Rattus rattus—was not commonly found in northern Europe.
The source of the plague has been identified by many sources as a specific ship carrying wool to Norway that departed London in May 1349. Somewhere en route, plague swept through the ship—one of the crew must have been infected but didn’t know it before embarking.