How the mighty Mongol empire failed spectacularly to invade Japan ... twice

The Mongol Empire began as a group of nomadic tribes on the Central Asian steppes, and Temujin united these tribes thanks to a combination of military victories and strategic alliances.

In 1206 he took the title of Genghis Khan, which meant 'universal ruler', and he led the Mongols on campaigns that overthrew powerful kingdoms and cities.

Mongol armies used swift cavalry, composite bows, and effective strategies that outmanoeuvred traditional medieval armies.

These factors made them a powerful enemy for states across Asia and Europe.

They defeated the Khwarazmian Empire, captured much of China, and destroyed major cities such as Baghdad in 1258. 

After Genghis Khan died in 1227, his descendants expanded the empire even further, dividing control among different branches of the family while maintaining their loyalty to the Great Khan.

Kublai Khan, a grandson of Genghis, completed the conquest of China and founded the Yuan dynasty in 1271.

He became the first non-Chinese emperor to rule all of China. His immense power gave him the resources to launch major overseas campaigns, and by the 1270s, he controlled Korea and large parts of Southeast Asia.

As he strengthened his rule over these territories, Kublai Khan looked across the sea to Japan as his next target. 

Japan in the late thirteenth century had a feudal political system in which the emperor held symbolic authority in Kyoto, but real power lay with the shogunate based in Kamakura.

The Hojo clan held the title of shikken, which meant 'regent', and they controlled the government on behalf of the shogun.

Samurai warriors provided the military backbone of this system, and they followed strict codes of loyalty and service to their lords. 

Japan had experienced relative stability during this period, yet its military forces had limited experience with large-scale foreign invasions.

Their armies focused mainly on internal conflicts between rival clans, and they trained for combat that praised individual bravery and personal reputation.

The Mongol threat presented a challenge that the samurai had never faced before, since the Mongols used massive archery and explosives combined with disciplined infantry tactics that differed greatly from traditional Japanese warfare. 

Kublai Khan wanted to bring Japan into the Mongol Empire as a tributary state, and he sent letters to the Japanese court in 1266 demanding submission.

The Japanese leaders ignored his demands, which Kublai Khan viewed as a personal insult to his authority.

He believed that Japan could provide valuable resources and profitable trade opportunities that would give strategic influence in East Asia. 

Control of Japan would also strengthen Mongol power in the Pacific region, and Kublai Khan hoped that a successful conquest would intimidate other neighbouring states that resisted Mongol control.

When diplomacy failed, he ordered his officials in Korea to build ships and assemble troops for a seaborne invasion. 

The first invasion took place in late 1274, when Kublai Khan gathered around 23,000 troops and 900 ships. He drew soldiers from China, Korea, and Mongolia.

The fleet crossed the Korea Strait and landed on Tsushima and Iki Islands, where the Mongols quickly overwhelmed the small Japanese garrisons.

After capturing the islands, the Mongols moved to Hakata Bay on the northern coast of Kyushu, where the Japanese defenders had prepared for an attack but were unready for the scale of the assault. 

The battle that followed shocked the Japanese warriors. Mongol troops fought in tight formations, used coordinated volleys of arrows, and deployed early gunpowder weapons such as exploding bombs.

Japanese samurai, who were used to single combat and personal duels, struggled against this style of warfare, and the Mongols inflicted heavy casualties while burning parts of Hakata. 

However, a sudden storm struck during the night, damaging the Mongol fleet, and the commanders feared that Japanese reinforcements might arrive in greater numbers.

They ordered a retreat to Korea, but the storm sank many ships and killed thousands of soldiers.

The Japanese credited the storm to divine intervention, calling it a kamikaze, which meant 'divine wind'. 

Kublai Khan was not satisfied with the outcome of the first invasion, and he ordered an even larger expedition while spending several years preparing for another assault.

Shipbuilders in Korea and China constructed thousands of vessels, and troops trained for a new campaign that placed heavy burdens on the populations forced to provide materials, labour, and supplies.

The preparations caused unrest in parts of the empire, as people grew resentful of the heavy demands imposed on them. 

In Japan, the shogunate understood that a second invasion was inevitable, and leaders ordered the construction of defensive walls along Hakata Bay.

They organised more samurai to be ready for battle, improved coastal watch systems, and kept troops on constant alert.

Fear of another Mongol attack unified the Japanese warrior class under the shogunate’s leadership, and the sense of urgency also strengthened the government’s authority over its vassals. 

The second invasion in 1281 dwarfed the first, as Kublai Khan assembled two separate fleets: one from Korea with around 900 ships and 40,000 troops, and another from southern China with 3,500 ships and 100,000 troops.

The plan required both fleets to meet off the coast of Kyushu and attack together, yet coordination problems slowed the campaign and caused delays that weakened the Mongols’ advantage. 

Japanese defenders fought fiercely when the Mongols tried to land, and the samurai launched night raids in small boats, setting enemy ships on fire and killing isolated groups of soldiers.

The Mongols found it difficult to establish a beachhead because of the defensive walls that had been built after 1274, and the long wait at sea left the fleets vulnerable. 

After several weeks, another powerful typhoon struck the area and destroyed much of the Mongol fleet again.

The storm sank hundreds of ships and drowned tens of thousands of soldiers, leaving survivors stranded along the coast where they were captured or killed by Japanese forces.

The disaster forced the remnants of the Mongol army to retreat in defeat. 

The invasions strengthened the authority of the Kamakura shogunate and the successful defence became a source of national pride that reinforced the idea that Japan enjoyed divine protection.

However, the campaigns placed great financial pressure on the government, which struggled to reward the samurai who had fought without gaining any new lands from conquest.

Discontent over unpaid service weakened the political stability of the regime in the following decades. 

Also, the concept of the kamikaze gained lasting cultural importance, as Japanese people believed that divine forces had protected the islands from foreign domination.

The memory of the invasions influenced Japanese attitudes toward defence and foreign threats for centuries, and it strengthened the belief that the islands were sacred. 

The failed invasions damaged Kublai Khan’s prestige and drained the empire’s resources since shipbuilding and troop mobilisation placed enormous burdens on the Yuan dynasty.

Thousands of conscripted workers died during the preparations, and the loss of ships and soldiers weakened Mongol military power in East Asia.

The defeats showed the limits of Mongol expansion when it relied on naval campaigns rather than cavalry-based warfare and showed that even the most powerful empire of the era could suffer major failure. 

Kublai Khan never attempted another invasion of Japan, and the disasters contributed to growing unrest within the Yuan dynasty.

The empire faced internal rebellions and economic problems that eroded its authority and reduced its ability to maintain control over its large territories in the decades that followed.