Onin war summary

The Onin War is the one of the most import war in the history of Japan. War destroyed the authority of of central government and the descent of the Japan into feudal warfare.

Before the Onin War, shogun kept peace by maintaining the balance of power between powerful clans such as the Hosokawa, Yamana, Hatakeyama and Shiba.

Shogun Ashikaga Yoshimasa
Shogun Ashikaga Yoshimasa

This political stability was challenged by repeated peasant uprising and division of court in two rival factions.

The Onin war began over the issue of who would succeed shogun Ashikaga Yoshimasa.

It was even more significant for the city of Kyoto, which was devastated by the war.

The war ended with no clear-cut winner. The armies of two rival factions simply fought themselves into exhaustion.

The biggest loser of this power struggle was shogun as he completely lost loyalty of peasants as well as nobles.

This destruction in power of shogunate resulted in emergence of new powers: the so-called sengoku daimyo or nobles and started Sengoku period- the Warring States period.

In Sengoku period, individual daimyo tried to dominate its neighbors which resulted in a mass power-struggle between the various powerful houses to dominate the whole of Japan.

Japan before the War

For centuries, the Japanese emperor ruled the country as the figurehead. The real power lay in the hand of Shogun, the military dictator who was selected by the emperor.

In reality, shogun has complete control of Japan and maintains emperors as figureheads.

Usually Shogun belongs to a powerful noble family and ruled the country through military might.

Shogun also had his own court and civil service, which helped him to run the country.

Why did the Onin war start

Even before the Onin War began, the system that helped the shogunate to rule the country became very unstable.

Small scale local conflicts were occurring throughout the Japan which threatening the stability of system.

Even greater threat was the regular occurrence of peasant uprising who demanded the return of land and cancellation of debts.

Just before the Onin War, the situation had become so unstable that uprisings struck Kyoto on an almost annual basis.

However Shogunate was successful in crushing the uprising every time it occurred. Situation became even more unstable when famine struck the country and starving people surging into Kyoto.

In hindsight, we can say that the ruling system of the Ashikaga shogunate had became so unstable that all it needed was the a single push to collapse it. The Onin War became that push; but neither the eighth shogun Yoshimasa nor other powerful nobles thought that whole structure of shogunate would collapse so easily.

A dispute between two powerful nobles Hosokawa Katsumoto and Yamana Sozen escalated into a civil war involving the Ashikaga shogunate in which large number of nobles from various regions of Japan fought each other.

Onin War - Hosokawa and Yamana Domain
Onin War – Hosokawa and Yamana Domain

In 1464, Japan was ruled by shogun Ashikaga Yoshimasa.

Shogun Ashikaga Yoshimasa persuaded his younger brother to leave the life of monk and join his court. Later, as Shogun Yoshimasa had no heir, so he named him as his heir.

However one year later, the unanticipated birth of a son to Shogun Yoshimasa put these plans on hold.

After birth of his son Shogun Yoshimasa wanted to make that son his heir. However his brother wanted to retain his claim of heir.

Soon two rival faction emerged in court one supporting shogun’s brother and another shogun;s son.

Soon two prominent nobles to the shogun, Hosokawa Katsumoto, and Yamana Sozen, join the opposing sides on the issue. Hosokawa backed the Shogun’s brother while Yamana backed the Shogun’s son for the position of heir of Shogun.

Already Hosokawa Katsumoto and Yamana Sozen had long standing unresolved conflict. The issue of who will succeed the shogun gave them a perfect excuse to resolve a long-standing conflict.

Both men wanted to strengthen their own position and control of the country after the death of the shogun Yoshimasa.

The succession issue started the Onin War and beginning of the Sengoku period.

The events of Onin Civil War

The shogun Yoshimasa tried to prevent the outbreak of hostility between two rival camps over the issue of his heir. However the situation soon escalated into a war as winner will hold complete control over the Shogunate.

By 1467, Japanese nobility split into two camps as the succession dispute became a pretext for a struggle for military supremacy.

Soon both camps started gathering their armies around the city of Kyoto, the center of national politics.

In attempted to prevent war, the shogun announced that whichever side started the war first that side will be labeled as rebel.

Both the side mobilized evenly matched army as Hosokawa had 85,000 troops under his command, while Yamana’s raised 80,000 troops for the coming war.

Due to threat by shogun a tense peace held for first few months but in March 1867, Yamana troops burn down the Hosokawa mansion.

As Yamana started the hostility, so shogun Yoshimasa declared Yamana (supporter of his son’s claim to shogunate) as rebel.

Two months later, troops loyal to Hosokawa burn down Yamana’s mansion.

In July, Shogun Yoshimasa appointed Hosokawa commanding general of his army in an attempt to stop further attacks from Yamana.

However, hostility soon turned into full fledge war as heavy fighting continued throughout July in Kyoto. Soon  the war destroyed several hundred large prominent  in Kyoto.

As the war continued Hosokawa established control over northeast portion of Kyoto around his mansion, while Yamana established controlled the south and west portion of the city.

By September, Yamana received reinforcements of 20,000 troops under Ouchi Masahiro.

Hosokawa also received reinforcements as his Akamatsu troops also arrived to Kyoto.

Soon they established balance of power and two adversaries faced one another without fight for the rest of the year.

During this war, the Shogun Yoshimasa was helpless in stooping the war.

While Kyoto was burning, Shogun Yoshimasa spent his time in cultural activities like poetry readings.

Hosokawa made two attempted to defeat Yamana forces but was unsuccessful in dislodge the Yamana army from Kyoto. For the most part the two armies fought each other to standstill and now kept glaring at one another for month after month.

Soon both armies dug a central trench which was ten feet deep and twenty feet wide to separate the two armies.

Finally, Shogun’s brother Yoshimi changed the side and joined Yamana. This act of his brother forced Shogun Yoshimasa to name his son Yoshihisa as his heir in 1469.

Now two brothers became figurehead of two separate warring factions. On the recommendation of shogun Yoshimasa, Emperor Go-Tsuchimikado stripped Yoshimi of his court ranks and declared him a rebel.

In 1473, both Yamana Sozen and Hosokawa Katsumoto died. Even after the death of two main rivals the war continued with no end in sight.

Eventually, the Yamana clan and nobles loyal to him start losing morale due to the tag of “rebel”.

One of the Yamana faction’s leading military commander Ouchi Masahiro, eventually burnt down area of Kyoto under his control and left Kyoto on 17 December 1477.

By 1477, ten years after the fighting had begun, Kyoto was left in ruin with nothing left to loot.

Neither clans were able to achieve its aims, other than to weaken each other and reduce the power of Shogunate.

Destruction of Kyoto in Onin War

One of the very distinct feature of Onin war was street fighting within city limits of Kyoto.

When the war started, the population of Kyoto was more than 100,000 people. However as the war progressed number of people living in Kyoto dropped dramatically.

Merchants who were the economic backbone of city fled the city which led to decline in economy of Kyoto.

Fortified mansions surrounded by stout wooden walls, ditches and tall observation towers became base of operations for both offense and defense.

Due to strong fortification, soon the conflict deteriorated into a stalemate where opposing force launched night raids. The opposing faction also used catapult to flung large stones to weaken their oppositions defenses.

During this conflict irregular troops called ashigaru needlessly burned down large section of Kyoto in careless attacks. These troops not only looted the enemy’s mansion but also temples and dwellings of common people.

Onin war, soon transformed into messy fight for survival with little room for rival armies to maneuver and dislodge their enemy.

The rich and elite of the city fled Kyoto and lived in the relative safety of the provinces.

Those people who could not escape were left behind to face disease and starvation. Armed robbers roamed the ruins and nothing was safe, not even the temples.

Soon these communities armed themselves to protect from bands of armed robbers and warriors.

Due to constant violence, no one dare to repair the damaged building. It took decades for Kyoto to recover and reach pre war level of prosperity.

Onin war spill into the Provinces

Even though main action was happening in Kyoto, but no part of Japan escaped the violence. Later as rival camp abandoned battles in Kyoto, the war had spread to the rest of Japan.

By 1485, warring army harassed the peasantry and jizamurai (lesser samurai) to such a extreme that they revolted.

Soon, to protect themselves, peasantry and jizamurai set up their own army called Ikki.

Later, these Ikki(army) forced the warring clan armies to leave the province.

Ikki was initially group of armed mob but over time through proper training they became a powerful force.

Within a year in 1486, they were successful in setting up a provisional government in Yamashiro province.

Two years later in 1488, another group called Ikko-ikki overthrew the provincial government in Kaga Province and took control of the province.

Ikko Ikki Warrior
Ikko Ikki Warrior

Soon after gaining control of this province, they began building a fortified temple complex near the Yodo River and made it as their headquarters.

Shogun failed in stopping both conflict of the nobles and uprising of the peasants.

Neither nobles nor a peasant has any reason to fear or obey a man who could not control the country.

Soon Nobles or Daimyos gathered their armies of samurai and supporting forces and went to war against either their less powerful neighbor or against their enemy to settle the score.

These war plunge Japan into decade long violence.

The breakdown of shogun’s authority over Japan provided huge opportunity to the pirates of the surrounding seas.

From 1470s onward, the piracy rose significantly around Japan over next century. Some of the powerful nobles also supported pirates, who acted as per the instruction of these nobles.

Who won the Onin War

By 1477, the Onin war came to end. Hosokawa Katsumoto , leader of one of the faction was dead but his faction won the war.

The Onin War, the power Ashikaga Shogunate was completely destroyed and the Hosokawa family became so powerful that they started treating the Ashikaga shoguns as their puppets.

Hosokawa clan appointed a deputy to run the government with shoguns acting as per his instructions.

The emporer was now the puppet of shogun, who in turn was the puppet of  Hosokawa clan.

In 1490, Ashikaga Yoshimi’s son Yoshitane became shogun. Soon he got involved in power struggle with the Hosokawa clan. In 1493, Hosokawa clan forced him to abdicate and sent him into exile. Soon they declared another Ashikaga, Yoshizumi, as new shogun

The Hosokawa clan was able to dominate the shogunate till 1558, when Oda Nobunaga, a leading Japanese daimyo oust them from Kyoto during Sengoku period.

Many great clans like Yamana, Isshiki, and Hatakeyama all disappeared after the Onin war whereas new clans such as the Takeda and Saito, rose to take their place.

These new clans have gained power and influence through violence and had no qualms about using it against their enemies.

However these constant warfare took massive toll on individual daimyo and weakened them to such an extent that powerful daimyo Oda Nobunaga found it easier to militarily assert a single, unified military government.

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