The Mongol Empire, once the largest contiguous land empire in history, began to fragment in the 1260s. Traditional explanations for its dissolution focus on internal strife following the death of Great Khan Mongke in 1259, a succession dispute that led to civil wars among his brothers, Kublai and Ariq Boke.
However, new evidence suggests an extraordinary natural event may have indirectly played a significant role in this collapse: the eruption of the Samalas Volcano in Indonesia. This cataclysmic eruption, one of the largest in recorded history, had far-reaching environmental effects that rippled across Eurasia, amplifying the political and social tensions already present within the Mongol Empire.
The Mongol Empire and Climate

Historians have long acknowledged the relationship between climate and the rise of the Mongol Empire. Favorable weather conditions in the early 13th century, including a warm and wet period, allowed the Mongols to sustain their herds and expand their conquests. Conversely, harsh conditions, such as droughts, often exacerbated conflicts among Mongol leaders. While climate has been explored as a factor in the empire’s growth and challenges, its role in the empire’s fragmentation has often been overlooked – until now.
A Volcano of Unprecedented Power

The eruption of the Samalas Volcano on the island of Lombok in late 1257 was a monumental event. It ranks as a magnitude 7 on the Volcanic Explosivity Index, surpassing more famous eruptions such as Tambora (1815) and Krakatoa (1883). Samalas ejected an unprecedented amount of sulfur into the stratosphere, disrupting global weather patterns. This led to a drop in temperatures and widespread ecological upheaval across the globe.
Climate Chaos Across Asia

The eruption’s impact was felt almost immediately. In China, severe droughts were followed by torrential rains and flooding in 1259, resulting in widespread crop failures and famine. In Korea, prolonged conflict with the Mongols compounded by food shortages led to the collapse of its military government. Meanwhile, in Japan, relentless rains and crop failures culminated in the Shōga famine, fostering unrest and banditry. These crises illustrate how the Samalas eruption created environmental stressors that destabilized societies across East Asia.
The Death of Mongke Khan

Amid this climate chaos, Great Khan Mongke led a campaign against the Song Dynasty in China. His army was stalled by heavy rains during the siege of Diaoyucheng in Sichuan province. The unrelenting downpours made military operations impossible and created unsanitary conditions that likely facilitated a cholera outbreak among Mongke’s troops. Mongke himself fell ill and died in August 1259, either from disease or complications stemming from these conditions. His death was a pivotal moment, leaving the empire without a clear successor and triggering a power struggle between his brothers.
The Role of Cholera

Cholera outbreaks have been linked to major volcanic eruptions in history, such as Tambora in 1815 and Pinatubo in 1991. The Samalas eruption likely created conditions for a similar outbreak by disrupting monsoon patterns and warming waters in the Bay of Bengal, which facilitated plankton blooms that harbored cholera bacteria. Trade routes could have carried this disease into China, where it devastated Mongke’s army. This indirect consequence of the eruption significantly altered the trajectory of Mongol history.
The Civil War That Followed

With Mongke’s death, his brothers Kublai and Ariq Boke both vied for the throne, plunging the empire into civil war. Kublai, based in northern China, had access to agricultural resources, while Ariq, stationed in Mongolia, faced a drought-stricken steppe. The environmental challenges, likely exacerbated by the Samalas eruption, contributed to Ariq’s defeat as his forces and livestock succumbed to starvation.
A Fragmented Empire

By the time Kublai emerged victorious in 1264, the Mongol Empire was irreparably fractured. While Kublai claimed the title of Great Khan, his control was limited to China and parts of Central Asia. The western territories of the empire had already splintered into independent Khanates, marking the end of a unified Mongol rule.
Global Implications of the Eruption

The Samalas eruption’s impact was not limited to Asia. In Europe, 1258 was marked by harsh winters, heavy rains, and widespread famine. England imported grain to stave off shortages, while flooding in the Holy Roman Empire devastated infrastructure. These interconnected crises highlight the far-reaching consequences of one volcanic eruption on global societies.
Climate as a Catalyst

The environmental disruptions caused by the Samalas eruption did not directly cause the Mongol Empire’s collapse, but they acted as a catalyst, exacerbating existing tensions. Mongke’s decision to attack the Song Dynasty and his failure to designate a successor were human choices. However, the eruption created the conditions that made these choices more consequential, accelerating the empire’s fragmentation.
A Lesson from History

The story of the Mongol Empire and the Samalas eruption shows us how a combination of human decisions and environmental factors can influence history. While leaders make choices that shape history, those choices are often influenced by natural events beyond their control. The collapse of the Mongol Empire serves as a reminder of how fragile even the most powerful empires can be when faced with environmental upheaval.
A Significant Role

Did the eruption of the Samalas Volcano end the Mongol Empire? Not directly. But its environmental impact played a significant role in shaping the conditions that led to the empire’s fragmentation. From devastating weather patterns to disease outbreaks, the eruption magnified existing challenges, pushing an already strained empire to its breaking point. It’s a powerful example of how the forces of nature can alter the course of human history in profound and unexpected ways.

Ed spent his childhood in the backwoods of Maine, where harsh winters taught him the value of survival skills. With a background in bushcraft and off-grid living, Ed has honed his expertise in fire-making, hunting, and wild foraging. He writes from personal experience, sharing practical tips and hands-on techniques to thrive in any outdoor environment. Whether it’s primitive camping or full-scale survival, Ed’s advice is grounded in real-life challenges.