Mongol invasions of Japan (Cherry, Plum, and Chrysanthemum)

Mongol invasions of Japan
Part of the Mongol invasion of East Asia and Kublai Khan's Campaigns
Samurai facing Mongol and Korean arrows and bombs
Date 1274, 1282 Location Kyūshū and southern Honshū, Japan Result Decisive Mongol Victory
Belligerents
Mongol Empire Yuan Dynasty Goryeo (Korea)	Japan Imperial Court in Kyoto Kamakura Shogunate
Commanders and leaders
Kublai Khan Kim Bang-gyeong	Emperor Kameyama Emperor Go-Uda Prince Koreyasu Hōjō Tokimune

The Mongol invasions of Japan (元寇, Genkō), which took place in 1274 and 1282, 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. The first invasion was a military failure for the Mongols and the Koreans. However, the second invasion was a success after better preparations by the Mongols strategically and technologically.

The invasions are of macro-historical importance because it showed the greatest extent of Mongol rule at its peak. The invasions were one of the earliest cases of gunpowder warfare outside of China. One of the most notable technological innovations during the war was the use of explosive, hand-thrown bombs.

Background

Kublai Khan (1215–1294)

In 1231, the Mongols crossed the Yalu River and extended their rule to the Korean Peninsula. The Korean royal court took refuge in Ganghwa Island and maintained their status quo from the mouth of the Han river. For two decades, the Koreans resisted the Mongol invasion until King Gojong decided to make a peace in 1258. After the Goryeo monarchs of Korea were made vassals of the Mongols, Kublai Khan (1215–1294), the grandson of Genghis Khan was elected new Great Khan in 1259.

While his successors expanded their conquests westward, Kublai had his sole interest to the east especially after the Goryeo Dynasty was made a vassal state. When the whole peninsula was subjugated in 1270, Kublai established the Yuan Dynasty in 1271 in northern China. Kublai’s desire to expand his empire began to grow with the founding of this new dynasty. When he was in the middle of subjugating southern China, the Great Khan’s eyes also pointed toward an archipelago nation across Korea: Japan.

Letter from Kublai Khan of the "Great Mongol State" (大蒙古國) to the "King of Japan" (日本國王), written in Classical Chinese, dated 8th month of 1266.

Japan had close economic and cultural ties with the East Asian continental nations since the ancient time. However, it maintained no official diplomatic relations with either the Yuan Dynasty or Goryeo by the time of Kublai Khan’s ascendance. In 1266, the Khan sent two of his envoys to Japan to establish “friendly relations” with Japan. In his letter brought along by the envoys, the Khan addressed the “King of Japan” to submit tribute to him and threatened invasion for the failure to accept that demand. While the court in Kyoto rejected the demand from the Mongols, it still drafted a conciliatory reply to the Khan. The court tried to minimize the possibility of invasion by the Mongols.

Hōjō Tokimune, the regent of the Bakufu, was unmoved by the demand and simply ignored it; the bakufu overruled the court by having the message draft not being sent to the Khan. Prior to 1274, subsequent Mongol diplomatic missions to Japan were rejected by the bakufu; Tokimune refused to have any compromise with the Mongols. Bad attitudes of the Bakufu toward the Mongol embassies took the patience out of Kubilai Khan. Japan seems ready to face any consequence, including a military campaign. As the time progressed, both sides has sensed that an invasion to Japan came near.

At the dawn of the invasion, the Bakufu undertook serious defensive preparations. The troops were mobilized by the Bakufu in northwestern Kyushu and was put on military alert since 1272. On other hand, the Mongols are nomadic people of the steppe by nature, not a seafaring one. As they possessed no knowledge in seafaring, Kublai Khan ordered King Wonjong of Goryeo to prepare the warships and to raise the invasion forces as well as the sailing crews. On November 2, 1274, the invasion finally began. An armada of about 800 vessels departed from a port in Korea, carrying about 40,000 men with about a half them were Korean.

First invasion (1274)

The Mongol fleet destroyed in a typhoon during the first invasion of Japan, 1274.

Kublai’s armada first raided some small islands off the Kyushu coast such Tsushima and Iki as well as the Matsuura Peninsula and the island of Takashima. On November 19, the Khan’s invading forces landed at Hakata in the northwest of Kyushu. More advanced warfare technology brought along by the invading forces initially forced the Japanese inland after a fierce battle in the Hakata Bay. However, at the night after the battle, a great storm hit the forces, destroyed many vessels and forced the Mongols to retreat.

The invasion had failed to submit the Japanese under the Mongol rule. However, Kublai Khan decided it will be not the last and only military campaign for Japan. He sent another diplomatic mission to Japan with same demand for submission in 1275. Tokimune harshly responded this mission by executing Kublai’s envoys. Although the Khan did not learn the death of his envoys several years later, he already ordered Wonjong's successor, Yeongjong, to prepare for another invasion.

In 1279, southern China has been conquered by the Yuan Dynasty which increased the Khan’s manpower for a new invasion. At the same time, Japan entered an era of peace in which the Bakufu used to strengthen its military preparation. A defensive wall was constructed in northwest Kyushu, including the area where the first Mongol invasion took place. By February 1281, the armada has been ready for the invasion and the Khan prepared to order it to attack Japan. However, his generals advised him for not attacking the Japanese by spring in order to caught them by surprise.

Kublai ignored the advice at first, but he increasingly convinced to delay the invasion by six months in order to suppress the remaining resistance in southern China. In August 1281, the Khan decided to further delay the invasion as he believed the armada will be swept out by the storm again during the rainy season between the late summer and early autumn. He then planned the invasion to set off in late winter; the Khan thus delayed the invasion for a year.

Second invasion (1282–1283)

The Second Battle of Hakata Bay where the Mongols and the Japanese fought along Genkō Bōrui, a defensive wall at the Hakata Bay.

On February 13, 1282, the second invasion of Japan began after been delayed for about a year. The armada comprised of 40,000 men sailed in about 900 vessels departed from Korea albeit a freezing climate. Similarly with the first invasion, the invading forces attacked Tsushima on May 3 and Iki on May 8. At Iki, the first force from Korea waited for the second force from southern China until the latter arrived at Hirado on April 1. The southern force was much stronger with 100,000 men sailed in about 3,500 ships.

The combined fleets invaded together the island of Takashima in early April 1282. Takashima was easily conquered by the invaders on April 18, 1282. Any landing to Kyushu proper by the Yuan forces now was inevitable. Continuing to advance, the invading forces successfully landed in Hakata on April 23, 1282. Albeit a fierce and brave resistance by the Japanese at the Second Battle of Hakata Bay, the Mongols overpowered them once again with greater manpower and superior technology.

The Japanese suffered heavy casualties during the battle and decided to retreat. With the victory in Hakata, the Mongols just opened the door for the real invasion and the Japanese, including the Emperor but not the bakufu, helplessly waited for a complete conquest of their island nation. When the dawn came in the day after the victory in Hakata, the invading forces quickly marched forward and easily captured Dazaifu on April 24, 1282. While the Bakufu insisted to continue the resistance, defeatist mood gradually growth around the court in Kyoto. Inflicted by the fall of Dazaifu, secret talks spread among the court aristocracy.

Emperor Go-Uda (1267–1324), reigning between 1274 and 1287.

The aristocratic class, called the kuge (公家), was always at odds with the bakufu and the buke which usurped the political power of them and of the sovereign. They planned the restoration of imperial powers before making peace with the Mongols. Emperor Go-Uda (1267-1324) and his father, abdicated Emperor Kameyama (1249-1305) who maintained cloistered rule over his son, silently supported the kuge. Plans to overthrow the dictatorship of the Regency were also discussed among the rival clans that deceived the Hōjō clan; the rival clans, however, did not have any future design about the fate of the bakufu itself.

Northern Kyushu was conquered by the Yuan forces as of June 1282. However, instead to attack Honshu immediately, the invading forces decided to consolidate their conquest in Kyushu. They waited until the next spring to cross from Kyushu to Honshu in the fear for stormy season in the sea. Dazaifu was made as the seat for the Yuan military office in Kyushu. Large fortifications were built by the Yuan forces around the Strait of Shimonoseki to stop the bakufu government from sending reinforcement army to Kyushu.

Remaining resistances in southern Kyushu, isolated from the island of Honshu, were mercilessly defeated by the Mongols between July 1282 to February 1283. The Yuan military office in Dazaifu then appointed officials from local people to help them running Kyushu. This period is called as the Pacification of Kyushu (九州平定, Kyūshū Heitei). Spring was finally break in March 1283; the Yuan forces prepared themselves to land in Honshu. Southern Honshu itself was already mobilized by August 1283; unable to find a way to send reinforcement troops to Kyushu, the bakufu was put into a defensive state.

Tokimune ordered the warriors from the western part of Honshu to protect the southern end of the island by January 1283. Defensive efforts proved to be fruitless; the Mongols defeated every resistances by the Japanese in southern Honshu. As the invading forces went closer to Kyoto, the commoners including of peasants and slaves from southern Honshu were drafted into service by the bakufu government. Large conscription although helped the war effort also crippled the economy as many farmers and fishermen were forced to leave their jobs to become soldiers.

The Mongol fleet crossed the Strait of Shimonoseki to southern Honshu.

Morale was low in Kyoto and the surrounding areas, especially after the Mongols landed in Honshu; the kuge abandoned any hope for victory over the Mongols. The aristocrats, including Takatsukasa Kanehira (1228-1294), the kampaku (関白, “imperial regent”) of the imperial government, plotted the assassination of Tokimune and the termination of bakufu government. On February 22, 1283, Tokimune was attacked by a band of men in his residence in Kamakura and got killed along with his family in an attempt to defend his life.

With the death of Tokimune, the Bakufu’s authority was weakened significantly. Kyoto decided to seek peace with the Yuan forces instead of having a prolonged war. The imperial court, however, did not want to participate directly in the peace-making effort. Instead to terminate the Bakufu completely like what desired by the kuge, Emperor Go-Uda simply put the Bakufu under the imperial control. He called the Bakufu officials to move from Kamakura to Kyoto in March 1283 so he could maintaining a direct surveillance of the Bakufu. The Emperor then sent his envoy to meet Miura Tanemura (1225–1297) in Nara.

Miura Tanemura (1225–1297), the shikken of Japan (1283–1297)

Tanemura was the last surviving member of Miura clan, the primary opponent of the Hōjō, that was destroyed by Hōjō Tokiyori in 1247. After the annihilation of his clan, Tanemura entered the priesthood and adopted the priestly name Myōkū. By 1283, he was almost sixty-year old. Nevertheless, as the only surviving member of main rival clan for the Hōjō, Tanemura rose as the most prominent figure among the buke. Emperor Go-Uda called Tanemura into his service and appointed him as new shikken of the bakufu. The shogun, Prince Koreyasu (1264-1326), as the titular head of the Bakufu pledged his loyalty to the Emperor shortly after the Bakufu offices were moved to Kyoto.

With the posts of shogun and shikken were occupied by men whose loyal to the imperial court, the military rule was completely put into the end and remained in the name only. Through the so-called Kamei Bakufu (掛名幕府, “nominal bakufu”) the Emperor indirectly made peace with the Yuan forces. Tanemura was ordered to sent the envoys to the military office of Yuan forces in southern Honshu, calling for peace with the Mongols, representing the Kamei Bakufu in the end of March 1283. The fighting was gradually ended by May 1283.

Aftermath

In June 1283, the Japanese envoys arrived in the continent; a peace treaty was concluded between the Yuan Dynasty and Japan. Japan accepted the Yuan overlordship over them and effectively became a vassal state of the Yuan Dynasty by summer 1283. In a reverse situation than before, the shogun as the head of bakufu was made the titular ruler of Japan by the Emperor in the vassal relationship with the Yuan Dynasty. 

Instead of having the Emperor or his children married the Mongol royalty, it was young Prince Koreyasu that got married in 1285 with Kubilai’s daughter, who popularly known as Princess Asako (朝子) (ca. 1270–1325). Asako’s real Mongol name was still unknown until today; her Japanese name was believed to be bestowed directly by Emperor Go-Uda. Her marriage with Koreyasu bore a son, Prince Masayasu (1289–1340), and three daughters to Prince Koreyasu. By doing so, the court felt they could at least maintaining some dignity in ruling their subjects and the purity of the imperial line.

While peace was restored between Japan and the Yuan Dynasty, diehard military warlords determined to keep fighting against the Yuan Dynasty as well as opposed the accumulation of the bakufu by the imperial court. Efforts to suppress these rebellions were made through joint military campaigns of the Japanese imperial forces and the Yuan forces in the time that is called the period of Pacification or known as the Kōwa era (講和) in Japan. Following the Pacification, Japan was put into a single, centralized government formally headed by the Emperor. The Kamei Bakufu then ordered the execution of local military leaders who refused to swear loyalty to the Emperor.

Further readings

• Farris, W. W. (2009). Japan to 1600: A Social and Economic History. Honolulu: University of Hawaii Press. ISBN 978-0-8248-3325-1 978-0-8248-3379-4
• Henshall, K. G. (2004). A History of Japan : From Stone Age to Superpower (2nd edition). New York: Palgrave Macmillan Limited. ISBN 1–4039–1272–6
• Meyer, M. W. (2009). Japan: A Concise History (Fourth Edition). Plymouth: Rowman & Littlefield Publishers. ISBN 978-0-7425-4117-7 978-0-7425-5793-2
• Sansom, G. B. (1974). A History of Japan to 1334. Tokyo: Charles E. Tuttle Company, Inc..