How the Medieval Warm Period (1000-1400 AD) Changed History

The World Before 1215

1215: Years that Changed History

Dr Dorsey Armstrong 2019

Film Review

This is a fascinating lecture series about world changing events occurring as a direct or indirect result of global warming (by 2 degrees F) between 1000 and 1400 AD.

The events included in the series include

the Magna Cartathe capture of Beijing by Genghis Khanthe Fourth Lateran Council (responsible for church weddings, the celibacy of Catholic priests and state-sanctioned persecution of Jews and MuslimPope Innocent’s call for the Fifth CrusadeZimbabwe’s rise to power in Africathe flowering of Pueblo culture in Americathe Golden Age of Islam, resulting in significant discoveries in medicine, math and astronomythe rise of the Samurai in Japan

In 1000 AD, the cities that flourished under the Roman empire had vanished. 95% of Europe (population 35 million) was rural, dependent on subsistence farming and (owing to low protein diets) likely to suffer from malnutrition.

However thanks to a warming period known as the Little Optimal, 300 years later Europe had a population of 80 million and London, Paris and Rome were booming. Improved crop yields and reduced infant mortality not only increased population size, but drove robust trade. By 1100, all previously unclaimed land had been claimed and land-owing aristocrats began to claim control over regional forests, which were rapidly cleared for food production.

The increase in trade and urban life meant that merchants, for the first time, could achieve the same economic status as land-owning noble. As the forests and access to wild food declined, real destitution appeared for the the first time. Beggars, who lost old  connections to communities and churches that kept them from starving, also began migrating to cities, where some supported themselves via gambling, prostitution and thievery. .

Warmer temperatures also led to an increase in overall fish stocks, a booming international herring and cod trade and advances in seafaring technologies.

Eric Thorvalsson (Eric the Red) established the first European colony in Greenland in 985, and in 1000 his son Leif Erickson established the first European settlement in North America (Newfoundland). Erickson named his new colony Vinland, intrigued to find wild grapes growing so far north.

In Europe, the population grew so rapidly that by the 13th century hunger had outstripped the land available. According to Armstrong, this led to the rise to Europe’s persecuting society, which stripped certain populations (lepers, pagans, Jews, heretic, pagans, single women, widows etc) of their right to productive land). This supposed improved access to land (and food) for the rest of society.

In the North American Southwest, global warming led to such severe drought that some civilizations abandoned 1000-year-old sites and relocated to find water.

Climate change also threatened the lifestyle of Mongolian nomads on the Central Asian plain. Forced them to expand westward because when traditional pastures ceased to support them, they brought Genghis Khan to power between 1162-1227. He, in turn,  create the largest empire ever in world history.

As the climate cooled around 1400 and the rains returned, life became easier in the Mongols’ traditional ancestral homeland (Outer Mongolia) and seems, according to Armstrong, to have ended their push westward.

Film can be viewed free with a library card on Kanopy.

https://www.kanopy.com/en/pukeariki/watch/video/12392969/12392971