Mongol Invasion of Japan

The 13th century became a golden period for the Mongols. The nation which previously was not taken into account quickly transformed into an expansive empire that was able to conquer the surrounding territories. Not only the Middle East and Central Asia were targeted, but other Asian regions did not escape the Mongol invasion. After successfully conquering China and Korea, Japan became the target of an invasion of the Mongols. Twice attempts were made, but due to the misfortune and will of nature, Kublai Khan failed to conquer Japan.

Background of the Mongol Invasion into Japan
After Genghis Khan's rule ended, the Mongols continued to expand their influence. In 1230, the Mongols succeeded in conquering northern China. A year ago they had crossed the Yalu River to expand their territory to the Korean Peninsula. The King of Korea (Koryo) is forced to be loyal to the Mongols, in return he can still rule as a vassal.

In 1259 Khubilai Khan, Genghis Khan's grandson, ascended the Mongol throne and became Emperor of Yuan China. Khubilai Khan ruled until 1294. Following the tradition of the Chinese emperor, he tried to force neighboring countries to submit. In line with this tradition, which is rationalized by the irrational argument of "heavenly mission,"

Kublai sent envoys to Japan accompanied by Korean officers as guides. They brought a message to establish trade relations and appealed to the "King of Japan" to surrender or the whole country would be invaded (Sasaki, 2008: 25). The ambassadors planned their departure from the Korean port in 1267, but weather conditions at sea forced them to return to the peninsula.


After the failure of the first departure, Khubilai was still trying to send his ambassadors to Japan until 1274. However, all his efforts were in vain, because all his envoys were never permitted by Japan to enter Kyoto, the imperial capital, or Kamakura, the center of Bakufu (military government) .

In fact, in 1268 the envoys were detained in Dazaifu, the residence of the Western Defense Commissioner on the island of Kyushu. The Khan's envoys were then moved to Kyoto, the residence of the Emperor and the court judge (Sansom, 1958: 400).

Fearing that the threat became real, the emperor tried to compromise by drawing up a draft to invite Khubilai to make peace. However, at that time the Emperor was only the symbolic ruler of the country, because the power was in the hands of Bakufu who was led by a military leader, Hojo Tokimune. Bakufu chose to disregard the imperial Draft and expel the Mongol envoys (Ibid .: 441).

In 1274, the Mongol emissary returned, but the military leader immediately ordered the deportation of the envoys as a form of humiliation against the Mongols. Such action means igniting the fires of war between the two parties. To anticipate the Mongol invasion, Bakufu then made various defense preparations.

War begins: First Mongol invasion 1274
To launch an invasion of Japan, Khubilai Khan needed ships and sailors (and soldiers). The Mongols are famous as land fighters who live in the savannah, arguably similar to Dothraki in the film Game of Thrones. They are not shipbuilders, they also do not have the knowledge and experience of shipping. Therefore, Khan ordered the King of Korea to build 900 fleets of warships and train his troops to be able to operate ships. (Sasaki, 2015: 25) Not only that, to supply the food supplies of his troops at sea, he also ordered large areas of the peninsula to be planted with rice.

In November 1274, a fleet of 40,000 people consisting of 20,000 Mongols and Chinese, 8,000 Korean soldiers, and around 7,000 Korean and Chinese seamen, departed from ports in Korea. The fleet used 300 large vessels and around 400-500 small vessels (Neuman: 1168).

The Kubilai fleet first invaded several small islands off the Kyushu coast destroying Japanese garrisons and then on November 19 landed at Hakata and Imazu in Kyushu. Armed with a large bow, Kublai Khan's troops were able to dominate the battle against the samurai.


Even according to some contemporary records, the Mongols brought with them poisonous weapons and paper and iron bombs thrown through throwers (Turnbull, 2010: 45). This is the first time that Japan has faced such weapons, so it is not surprising that Japanese forces are pressured.

In the midst of the precarious situation, the Kyushu Army desperately defended its territory, hoping that reinforcements from the central and eastern provinces would soon arrive.

When the Mongol army had the upper hand, Korean weather navigators suddenly asked the Mongol Generals to raise their troops back on board. They had predicted the arrival of a storm that could isolate them on the island if it did not sail immediately. Hearing the warning, finally the Mongol Generals ordered their troops to board the ship and sail again. But the decision seems to be late, because the storm has raged and submerged some Mongol ships trying to return to mainland Korea (Delgado, 2008: 96).

On the other hand, a storm saved Japanese troops from being destroyed in Kyushu. In the afternoon they saw people from the enemy fleet coming out of the bay because their ship sank in the open sea during a storm. They were later arrested and taken to Mizuki to be executed.

According to some records, two hundred people were missing. While according to Korean records, about 13,000 people from the occupation forces lost their lives during this expedition, most of them probably drowned (Sansom, 1958: 444). The Mongol invasion had failed and the remnants of the Kublai army returned to Korea empty-handed.

For the sake of Ambition: Second Invasion 1281
Khubilai believes the cause of the failure of his first invasion of Japan was a storm. Therefore, he again sent an envoy to Japan in 1275. The messenger brought a message from Khublai that Japan surrender and submit to his empire. Instead of getting a positive response, they were detained for four months before being beheaded in Kamakura (Delgado, 2008: 100).

Kublai still did not give up, in 1279 he again sent more messengers. They were not fared better and were executed on the beach in Hakata. A series of executions of his envoys brought Kublai to the conclusion, that Japan did not intend to submit to the Mongol empire. After conquering South China, Kublai immediately ordered residents of the Yangtze area to build 600 warships and King Koryo (Korea) to build 900 ships for the second invasion.

In the autumn of 1280 Kublai Khan held a high-level conference in one of his palaces to discuss further strategies against Japan. Departing from a bad experience in 1274, he planned a more mature strategy to deal with the fierce resistance of Japanese troops, in Tsushima, Iki, and Hakata. The military and naval resources of the Southern Song dynasty are now fully under Mongol control, so that Khubilai Khan can build attacks from Korea and southern China with large troops (Turnbull, p. 55).


Six hundred warships were ordered from southern China, in addition to 900 from Korea. Plus an estimated 40,000 troops on the eastern route from Korea and 100,000 South China. At least the Mongol forces in the second invasion were three times more than the 1274 troops. Arguably, the second invasion of Mongolia to Japan was like the sequel to the blockbuster film; bigger in scale, more players, bigger budget, and the same director (Kublai Khan).

The official order to attack Japan came out in the first month of 1281. The Eastern Route attack from Korea was carried out in a manner similar to the invasion of 1274. While the Yangzi troops would sail directly from southern China across 768 km (480 miles) of ocean to meet with the Eastern Route Army around Iki before joining for a massive landing on the Japanese mainland (Sasaki, 2015: 25).

Troops from Korea departed on May 22, 1281 according to plan, but it took longer to reach Tsushima than its predecessors in 1274. Tsushima was attacked on June 9 and Iki on June 14. Japanese troops led by Shoni Suketoki and Ryuzoji Suetoki were unable to withstand the onslaught of weapons of the Mongol army and they were killed in the raid.

The attack killed 300 residents. Some residents ran to escape to the mountains, but the Mongol soldiers who heard the children's cries looking for them and eventually killed the residents hiding in the mountains. As previously planned, the Eastern Route Army is expected to wait for the Southern Route Army which is expected to arrive on July 2 in Iki.

On the other hand, armed with experience from the attacks of 1274, Japanese troops have built Genkō Bōrui's defensive wall along the ship landing zone at Hakata. The wall was built for five years and has a length of about 20 kilometers.

In spring, the Eastern Route Forces had arrived at the meeting point, but the Southern troops were late to arrive at the specified date. However, troops from Korea seemed impatient to wait for the arrival of South Chinese troops, so a week before the planned meeting of the Southern and Eastern Mongol forces, the Commander of the Eastern Ruten Force instead decided to attack first (Sansom, 1958: 449). The attack did not make it easy for them to land, but instead broke the concentration of the troops.

The Japanese responded by sending a small boat full of samurai to attack and board the larger enemy ship. This strategy proved effective in preventing the Mongols from landing (Yamada, 1916: 185).


For weeks the Mongols had difficulty landing. This condition caused them frustration and eventually retreated to Iki island.

In mid-July, the Southern fleet arrived. The two fleets then joined forces to attack Hirado in early August and continued the attack on Takashima located on the northwest coast of Kyushu on August 12 (Turnbull, 2010: 70).

Fierce fighting raged for several weeks. The length of the siege caused the Mongol army to run low on food reserves. On the other hand, the war coincided with the hurricane season which could come at any time.


On August 14, a typhoon known to the Japanese population as Kamikaze (wind of the gods) struck the Mongol fleet on the coastline. It is not known exactly what happened to the Mongol fleet, but according to the Chronicles Yuan about 20,000-30,000 Mongol and Korean troops who survived the storm were captured and beheaded. While the Southern Song fleet which was once a Japanese business partner is still forgiven and only jailed.

More recent archaeological evidence shows that the fleet was largely destroyed not because of the strength of the wind alone, but also because of poor ship construction (Ibid: 78). This makes sense considering the Mongol warships were made in a hurry and in a short time.

The news of the withdrawal of the Mongols until finally arrived at the Japanese government on September 23, 1281. This victory was celebrated in the Iwashimizu temple as a form of gratitude to the gods. Japan's success in surviving surpassed everyone's expectations, so the story of kamikaze has been passed down until now.

On the other hand, Kublai Khan actually still wanted to make a third attempt, but his soldiers had experienced fatigue due to the failure of the two invasions. Finally he chose to focus on taking care of domestic problems which at that time were in chaos (Sansom, 1958: 450).