Was 536 CE the worst year in history? Thanks to massive volcanic eruptions, darkness spread across the former Roman empire for 18 months. The Krakatoa eruption of 535 AD was part of a spike in volcanic eruption activity that continued for a decade. Some scholars even believe a comet struck the Earth, causing the 536 AD dust cloud. Whatever the exact cause, a fog blanketed Eurasia for over a year. Temperatures dropped, causing crop failures and massive famines.
Across Eurasia, societies nearly collapsed. Irish chronicles lamented "a failure of bread from the years 536–539." In China, 80% of the population starved. It snowed in Mesopotamia. And then a plague swept across the world, wiping out 50 million people. How did humankind recover after this devastating series of disasters? And how long did the recovery take?
In 536 CE, an Icelandic volcano spewed enough ash into the air to block out the light in Europe for 18 months. According to Procopius, a Byzantine historian who witnessed the darkness, “the sun gave forth its light without brightness, like the moon, during this whole year."
Additional volcanic eruptions in the 540s kept temperatures low for a decade. The volcanoes eventually stopped erupting, but the damage they caused lasted for years. The decade following 536 was the coldest on record for 2,000 years, and it took until well into the 7th century for signs of climatic and economic improvements.
The 6th century Byzantine writer John Lydos declared, "If the sun becomes dim... as happened in [536/537] for nearly a whole year... so that produce was [depleted] because of the bad time - it predicts heavy trouble in Europe."
In Rome, Cassiodorus wrote, "We marvel to see no shadows of our bodies at noon." The volcanic eruptions left a thick fog over Europe that barely burned off during the day. Cassidorus reported that "seasons seem to be all jumbled up together."
After 18 months, the fog finally began to recede. Additional volcanic eruptions in 540 and 547 kept temperatures lower across Europe and Asia, but at least the dust veil lifted.
A climate crisis and famine followed the 536 volcanic eruption, ending millions. And then plague broke out in 541.
The afflicted experienced delusions, fevers, and swollen lymph nodes, according to Procopius, who lived through the plague. Eventually called Justinian's Plague, the disease claimed as many as 50 million people.
The plague eliminated as much as 40% of Constantinople's residents in just four months before it burned out. While Constantinople recovered, the epidemic continued to appear across Europe and the Mediterranean world for several centuries. The same disease would return in the 14th century as the Black Plague.
Over a year of darkness followed the 536 eruption of a volcano in Iceland. According to John of Ephesus, "The sun was dark and its darkness lasted for eighteen months; each day it shone for about four hours, and still this light was only a feeble shadow... the fruits did not ripen and the wine tasted like sour grapes."
Average summer temperatures in Central Asia dropped around 4 degrees. Crops didn't grow and famine quickly followed.
The climate eventually recovered, but it took over a century. Today, scholars point to 536 as the beginning of the Late Antique Little Ice Age, which lasted until 660 in western Europe.