The Genpei War in Japan, 1180 - 1185

Scene from the Genpei War.

Wikimedia Commons / CC BY 4.0

Date: 1180-1185

Location: Honshu and Kyushu, Japan

Outcome: Minamoto clan prevails and almost wipes out Taira; Heian era ends and Kamakura shogunate begins

The Genpei War (also romanized as "Gempei War") in Japan was the first conflict between large samurai factions. Although it happened nearly 1,000 years ago, people today still remember the names and accomplishments of some of the great warriors who fought in this civil war.

Sometimes compared with England's "War of the Roses," the Genpei War featured two families fighting for power. White was the clan color of the Minamoto, like the House of York, while the Taira used red like the Lancasters. However, the Genpei War predated the Wars of the Roses by three hundred years. In addition, the Minamoto and Taira were not fighting to take the throne of Japan; instead, each wanted to control the imperial succession.

Lead-up to the War

The Taira and Minamoto clans were rival powers behind the throne. They sought to control the emperors by having their own favorite candidates take the throne. In the Hogen Disturbance of 1156 and the Heiji Disturbance of 1160, though, it was the Taira who came out on top. 

Both families had daughters who had married into the imperial line. However, after the Taira victories in the disturbances, Taira no Kiyomori became the Minister of State; as a result, he was able to ensure that his daughter's three-year-old son became the next emperor in March of 1180. It was the enthronement of little Emperor Antoku that led the Minamoto to revolt.

War Breaks Out

On May 5, 1180, Minamoto Yoritomo and his favored candidate for the throne, Prince Mochihito, sent out a call to war. They rallied samurai families related to or allied with the Minamoto, as well as warrior monks from various Buddhist monasteries. By June 15, Minister Kiyomori had issued a warrant for his arrest, so Prince Mochihito was forced to flee Kyoto and seek refuge in the monastery of Mii-dera. With thousands of Taira troops marching toward the monastery, the prince and 300 Minamoto warriors raced south toward Nara, where additional warrior monks would reinforce them.

The exhausted prince had to stop to rest, however, so the Minamoto forces took refuge with the monks at the easily defensible monastery of Byodo-in. They hoped that monks from Nara would arrive to reinforce them before the Taira army did. Just in case, however, they tore the planks from the only bridge across the river to Byodo-in.

At first light the next day, June 20, the Taira army marched quietly up to Byodo-in, hidden by thick fog. The Minamoto suddenly heard the Taira war-cry and replied with their own. A fierce battle followed, with monks and samurai firing arrows through the mist at one another. Soldiers from the Taira's allies, the Ashikaga, forded the river and pressed the attack. Prince Mochihito tried to escape to Nara in the chaos, but the Taira caught up with him and executed him. The Nara monks marching toward Byodo-in heard that they were too late to help the Minamoto, and turned back. Minamoto Yorimasa, meanwhile, committed the first classical seppuku in history, writing a death poem on his war-fan, and then cutting open his own abdomen.

It seemed that the Minamoto revolt and thus the Genpei War had come to an abrupt end. In vengeance, the Taira sacked and burned the monasteries that had offered aid to the Minamoto, slaughtering thousands of monks and burning Kofuku-ji and Todai-ji in Nara to the ground.

Yoritomo Takes Over

The leadership of the Minamoto clan passed to the 33-year-old Minamoto no Yoritomo, who was living as a hostage in the home of a Taira-allied family. Yoritomo soon learned that there was a bounty on his head. He organized some local Minamoto allies, and escaped from the Taira, but lost most of his small army in the Battle of Ishibashiyama on September 14. Yoritomo escaped with his life, fleeing into the woods with Taira pursuers close behind. 

Yoritomo made it to the town of Kamakura, which was solidly Minamoto territory. He called in reinforcements from all of the allied families in the area. On November 9, 1180, at the so-called Battle of the Fujigawa (Fuji River), the Minamoto and allies faced an over-extended Taira army. With poor leadership and long supply lines, the Taira decided to withdraw back to Kyoto without offering a fight. 

A hilarious and likely exaggerated account of the events at Fujigawa in the Heiki Monogatari claims that a flock of water-fowl on the river marshes was started into flight in the middle of the night. Hearing the thunder of their wings, the Taira soldiers panicked and fled, grabbing bows without arrows or taking their arrows but leaving their bows. The record even claims that Taira troops were "mounting tethered animals and whipping them up so that they galloped round and round the post to which they were tied."

Whatever the true cause of the Taira retreat, there followed a two-year lull in the fighting. Japan faced a series of droughts and floods that destroyed the rice and barley crops in 1180 and 1181. Famine and disease ravaged the countryside; an estimated 100,000 died. Many people blamed the Taira, who had slaughtered monks and burned down temples. They believed that the Taira had brought down the wrath of the gods with their impious actions, and noted that Minamoto lands did not suffer as badly as those controlled by the Taira.

Fighting began again in July of 1182, and the Minamoto had a new champion called Yoshinaka, a rough-hewn cousin of Yoritomo's, but an excellent general. As Minamoto Yoshinaka won skirmishes against the Taira and considered marching on Kyoto, Yoritomo grew increasingly concerned about his cousin's ambitions. He sent an army against Yoshinaka in the spring of 1183, but the two sides managed to negotiate a settlement rather than fighting one another.

Fortunately for them, the Taira were in disarray. They had conscripted a huge army, marching forth on May 10, 1183, but were so disorganized that their food ran out just nine miles east of Kyoto. The officers ordered the conscripts to plunder food as they passed from their own provinces, which were just recovering from the famine. This prompted mass desertions.

As they entered Minamoto territory, the Taira divided their army into two forces. Minamoto Yoshinaka managed to lure the larger section into a narrow valley; at the Battle of Kurikara, according to the epics, "Seventy thousand horsemen of the Taira perish[ed], buried in this one deep valley; the mountain streams ran with their blood..."

This would prove the turning point in the Genpei War.

Minamoto In-Fighting

Kyoto erupted in panic at the news of the Taira defeat in Kurikara. On August 14, 1183, the Taira fled the capital. They took along most of the imperial family, including the child emperor, and the crown jewels. Three days later, Yoshinaka's branch of the Minamoto army marched into Kyoto, accompanied by the former Emperor Go-Shirakawa.

Yoritomo was nearly as panicked as the Taira were by his cousin's triumphal march. However, Yoshinaka soon earned the hatred of the citizens of Kyoto, allowing his troops to pillage and rob people regardless of their political affiliation. In February of 1184, Yoshinaka heard that Yoritomo's army was coming to the capital to expel him, led by another cousin, Yoritomo's courtly younger brother Minamoto Yoshitsune. Yoshitsune's men quickly dispatched Yoshinaka's army. Yoshinaka's wife, the famous female samurai Tomoe Gozen, is said to have escaped after taking a head as a trophy. Yoshinaka himself was beheaded while trying to escape on February 21, 1184.

End of the War and Aftermath:

What remained of the Taira loyalist army retreated into their heartland. It took the Minamoto some time to mop them up. Almost a year after Yoshitsune ousted his cousin from Kyoto, in February of 1185, the Minamoto seized the Taira fortress and make-shift capital at Yashima. 

On March 24, 1185, the final major battle of the Genpei War took place. It was a naval battle in the Shimonoseki Strait, a half-day fight called the Battle of Dan-no-ura. Minamoto no Yoshitsune commanded his clan's fleet of 800 ships, while Taira no Munemori led the Taira fleet, 500 strong. The Taira were more familiar with the tides and currents in the area, so initially were able to surround the larger Minamoto fleet and pin them down with long-range archery shots. The fleets closed in for hand-to-hand combat, with samurai leaping aboard their opponents' ships and fighting with long and short swords. As the battle wore on, the turning tide forced the Taira ships up against the rocky coastline, pursued by the Minamoto fleet.

When the tides of battle turned against them, so to speak, many of the Taira samurai jumped into the sea to drown rather than being killed by the Minamoto. The seven-year-old Emperor Antoku and his grandmother also jumped in and perished. Local people believe that small crabs that live in the Shimonoseki Strait are possessed by the ghosts of the Taira samurai; the crabs have a pattern on their shells that looks like a samurai's face.

After the Genpei War, Minamoto Yoritomo formed the first bakufu and ruled as Japan's first shogun from his capital at Kamakura. The Kamakura shogunate was the first of various bakufu that would rule the country until 1868 when the Meiji Restoration returned political power to the emperors.

Ironically, within thirty years of the Minamoto victory in the Genpei War, political power would be usurped from them by regents (shikken) from the Hojo clan. And who were they? Well, the Hojo were a branch of the Taira family.


Arnn, Barbara L. "Local Legends of the Genpei War: Reflections of Medieval Japanese History," Asian Folklore Studies, 38:2 (1979), pp. 1-10.

Conlan, Thomas. "The Nature of Warfare in Fourteenth-Century Japan: The Record of Nomoto Tomoyuki," Journal for Japanese Studies, 25:2 (1999), pp. 299-330.

Hall, John W. The Cambridge History of Japan, Vol. 3, Cambridge: Cambridge University Press (1990).

Turnbull, Stephen. The Samurai: A Military History, Oxford: Routledge (2013).

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Szczepanski, Kallie. "The Genpei War in Japan, 1180 - 1185." ThoughtCo, Apr. 5, 2023, Szczepanski, Kallie. (2023, April 5). The Genpei War in Japan, 1180 - 1185. Retrieved from Szczepanski, Kallie. "The Genpei War in Japan, 1180 - 1185." ThoughtCo. (accessed June 7, 2023).