The Mongol invasions of Japan which took place in 1274 and 1281, were major military efforts undertaken by Kublai Khan of the Yuan dynasty to conquer the Japanese archipelago after the submission of the Korean kingdom of Goryeo to vassaldom. Ultimately a failure, the invasion attempts are of macro-historical importance because they set a limit on Mongol expansion and rank as nation-defining events in the history of Japan. The invasions are referred to in many works of fiction and are the earliest events for which the word kamikaze (“divine wind”) is widely used, originating in reference to the two typhoons faced by the Mongol fleets.
The Mongol Empire
Kublai Khan became Emperor of China in 1259 and established his capital in Beijing in 1264 . Korea was then forced to submit to Mongol power. Two years later, he sent envoys to Japan to submit to the Mongol rule, or to face colonial rule. The second group of envoys was sent in 1268, returning empty-handed, as before. The two envoys met Chinzei Bugy, or Defense Commissioner for the West, who sent messages to the Shogun in Kamakura , and the Emperor in Kyoto. Some envoys were later sent, some through Korean envoys , and some by Mongol ambassadors. The Bakufu (Shogun government) ruled over all the fiefs in Kyushu (the area closest to Korea, and thus most likely to be attacked) to return to their colonies, and troops in Kyushu moved west, increasing control at landing points most likely. In addition, mass prayer services were organized, and many government jobs were set aside to deal with the crisis.
The Khan was willing to go to war as early as 1268 , but found that the Koreans did not have the resources to supply them with sufficient troops and navy at that time. He sent troops to Korea in 1273 , to act as front guards, but they failed to get enough food for themselves and their horses in rural areas of Korea, and had to return to China for supplies. The number of horses needed to support the Mongol army, and the necessary pasture to limit the movement of troops in barren areas where almost nothing grows.
The First Invasion (Bunei Campaign)
Finally, in 1274, the Mongol fleet sailed out, with about 15,000 Mongol and Chinese troops and 8,000 Korean troops, in 300 large ships and 400–500 smaller ships. They conquered the islands of Tsushima and Iki easily, and landed on November 19 in Hakata Bay, not far from Dazaifu, Kyushu’s former administrative center. The next day the Battle of Bun’ei took place, also known as the “Battle of Hakata Bay”; the Mongols had better tactics and weapons, but their numbers were much smaller than those Japanese warriors who had been prepared for the attack for several months, and also received aid as soon as they heard the news of the fall of Tsushima and Iki. The Japanese managed to survive all day, and the storm that night forced the Mongol army to retreat.
Kublai Khan then returned to diplomacy and sent another embassy to Japan in 1275 CE demanding, once again, tribute be paid. This time the shogunate was even more dismissive in its reply and beheaded the Mongol ambassadors on a beach near Kamakura. The Khan was undeterred and sent a second embassy in 1279 CE. The messengers met the same fate as their predecessors, and the Khan realised only force would bring Japan into the Mongol Empire.
The Second Invasion (Koan Campaign)
Beginning in 1275, Bakufu stepped up efforts to defend the second occupation they were confident would come. In addition to the better management of the samurai in Kyushu, they ordered the construction of defensive structures at most possible landing places, including Hakata. Meanwhile, the king of Korea tried several times to negotiate with the Mongols, opposing further colonial attempts against Japan. Kublai Khan’s second invasion fleet was a whole lot bigger than the first one. This time, thanks to his recent defeat of the Song and acquisition of their navy, there were 4,400 ships and around 100,000 men, again a mix of Mongol, Chinese, and Korean warriors.
In the spring of 1281 , the Mongol Chinese fleet was blocked due to difficulties in supplying and operating a large number of ships . The Korean fleet instead sailed, and faced great destruction at Tsushima, before turning back. In the summer, the Korean / Chinese coalition fleet conquered Iki-shima, and moved to Kyushu, where they landed in several positions. In a number of individual battles, collectively known as the Battle of Koan, or the Second Battle of the Gulf of Hakata, the Mongol forces retreated back to their ships. The famous Kamikaze storm , a violent hurricane, then hit the coast of Kyushu for two consecutive days, destroying most of the Mongol fleet.
The storm winds that either sunk or blew the Mongol ships safely away from Japanese shores were given the name kamikaze or ‘divine winds.’ as they were seen as a response to the Japanese appeal to Hachiman, the Shinto god of war, to send help to protect the country against a vastly numerically superior enemy. The name kamikaze would be resurrected for the Japanese suicide pilots of the Second World War (1939–1945 CE) as they, too, were seen as the last resort to once again save Japan from invasion.