Plague, hunger, war, harsh climate, all took place in a time that researchers rated as the worst in human history.
Research by a Harvard University professor shows that 536 is the worst time in human history. Europe, the Middle East and parts of Asia are darkened by the mysterious fog .
Volcanic eruption in Iceland phase 6 can create the worst period in human history.
It also causes snowfall in China, causing crop failures, severe droughts, epidemics and famines to spread throughout the northern hemisphere.
That gloomy period triggered from an Icelandic volcanic eruption, creating a century of starvation and death.
Michael McCormick, an archaeologist from Harvard University and a medieval historian, told Science that the world showed no signs of recovery until 640.
'It is the worst stage in human history , the worst period for survival , ' McCormick said.
The fog caused the northern hemisphere to sink in darkness for 18 months, all day and night.
The temperature in the summer of 536 averaged 1.5-2.5 degrees Celsius, the lowest level in 2,300 years.
The world is dark in the period of 536.
This period of global disaster is also known as the 'dark age' . The exact cause of this event is a mystery to scientists, until new research by McCormick and colleagues.
Specifically, the researchers believe that the 536 volcanic eruption in Iceland was the main agent . The volcano continued to erupt in 540 and 547 years.
Millions of tons of ash spread throughout the world, creating a bad period for a century.
The research is published in detail in Antiquity magazine.