Honno-ji Incident (1582): The Betrayal and Death of Oda Nobunaga

The Honno-ji Incident was the attack on 21 June 1582 in which Akechi Mitsuhide, a senior general of Oda Nobunaga, surrounded the Honno-ji temple in Kyoto and forced his lord’s death. Nobunaga, then the most powerful man in Japan, died in the burning temple, and his heir was killed the same day. The coup ended Nobunaga’s drive to unify the country and opened a struggle for power won by Toyotomi Hideyoshi.

Background: Nobunaga at the height of his power

By 1582 Oda Nobunaga controlled most of central Japan. In the spring his armies destroyed the Takeda clan in the east, and he ruled from his new castle at Azuchi on Lake Biwa.

Only a few great independent lords remained. In the west, his general Hashiba Hideyoshi, later Toyotomi Hideyoshi, was besieging Takamatsu Castle in the lands of the Mori clan. In June Hideyoshi asked for reinforcements, and Nobunaga ordered several commanders, including Akechi Mitsuhide, to prepare to march west. Nobunaga himself set out for Kyoto on the way to join the campaign.

In mid-June, on the 29th day of the 5th month in the Japanese calendar, he arrived in Kyoto with a small escort, probably no more than a hundred or so attendants and guards. He lodged at Honno-ji, a temple of the Hokke (Nichiren) school that he had used before. His eldest son and heir, Oda Nobutada, stayed at the Myokaku-ji temple nearby.

Akechi Mitsuhide

Akechi Mitsuhide was one of Nobunaga’s most trusted commanders. A cultured man with links to the court and to the former shogun Ashikaga Yoshiaki, he had served Nobunaga since about 1568. He had taken part in the Siege of Mount Hiei and been rewarded with Sakamoto and later with the province of Tanba, where his base was Kameyama Castle.

He was assembling an army of around 13,000 men at Kameyama, officially to join Hideyoshi in the west.

Shortly before, in early June 1582 (the 5th month in the Japanese calendar), Mitsuhide had been put in charge of entertaining Tokugawa Ieyasu during a visit to Azuchi, and was then relieved of the task and sent to prepare for the western campaign. Later writers saw this as a humiliation, though contemporary evidence for any quarrel is thin. In the days before the attack he took part in a linked-verse (renga) poetry gathering at a shrine on Mount Atago, near Kyoto; one of his verses has often been read as a hint of his plan, but this interpretation is disputed.

What happened on 21 June 1582

On the evening of 20 June Mitsuhide’s army left Kameyama. Instead of taking the road west, it crossed the hills eastwards towards Kyoto. Later accounts say that Mitsuhide told his troops “the enemy is at Honno-ji”, but this famous line is not found in contemporary records.

In the early hours of 21 June, the 2nd day of the 6th month in the Japanese calendar, Akechi troops surrounded Honno-ji. According to the chronicle of Nobunaga’s retainer Ota Gyuichi, Nobunaga at first thought the noise was a quarrel among servants. When told the attackers carried Akechi banners, he is recorded as saying words usually translated as “It cannot be helped”.

Nobunaga fought with a bow and then a spear until he was wounded. He then withdrew into the inner rooms as the temple burned. He is generally believed to have taken his own life, aged 47, but his body was never found. His young page Mori Ranmaru and most of the defenders were killed.

Nobutada, at Myokaku-ji, moved to the stronger Nijo Palace nearby. After arranging for the imperial prince living there to leave safely, he and his men fought until the palace was overwhelmed, and he too took his own life.

Theories about Mitsuhide’s motive

Mitsuhide left no explanation, and his motive has been debated ever since. The main theories include:

• Grudges. Later stories describe Nobunaga humiliating Mitsuhide in public, but most of these come from sources written long after the event.
• Ambition and fear. Mitsuhide may have seen a rare chance to seize power, or feared that he would be demoted or moved, as other senior vassals had been.
• The Shikoku question. Mitsuhide had acted as Nobunaga’s go-between with the Chosokabe clan of Shikoku. Nobunaga had recently turned against the Chosokabe and was preparing an invasion. Letters published in 2014 have strengthened the view that this shift damaged Mitsuhide’s position.
• Conspiracy theories. Some writers have proposed that the imperial court, the former shogun Ashikaga Yoshiaki, Hideyoshi or others were behind the attack. None of these theories is supported by firm evidence.

The struggle that followed

Mitsuhide occupied Kyoto and Azuchi Castle and tried to win over other lords and the court, but few joined him. Tokugawa Ieyasu, Nobunaga’s ally, was visiting Sakai near Osaka with a small party. He escaped through the mountains of Iga province, a dangerous journey known as the “crossing of Iga”, and reached his own lands safely.

Hideyoshi reacted fastest. On hearing the news he made peace with the Mori and marched his army back towards Kyoto in little more than a week. On 2 July 1582 he defeated Mitsuhide at the Battle of Yamazaki, south-west of the capital. Mitsuhide fled and was killed, reportedly by villagers, at Ogurusu near Kyoto.

Because Mitsuhide held power for less than two weeks, Japanese tradition speaks of his “three-day rule”, an expression still used for a very short-lived success.

In July Nobunaga’s senior vassals met at Kiyosu Castle to settle the succession. Hideyoshi supported Nobutada’s infant son, Sanboshi, as head of the Oda house, which left real power with the generals. Within a year Hideyoshi had defeated his main rival, Shibata Katsuie, and become the dominant figure in Japan.

Legacy and the site today

The temple that Nobunaga knew no longer exists. In the 1590s Hideyoshi had Honno-ji rebuilt on a new site in central Kyoto, as part of his reorganisation of the city’s temples. The present temple holds a memorial to Nobunaga and those who died with him, while a stone marker stands at the original location. Excavations near the old site have found burned roof tiles and remains of ditches from the period.

The incident has remained one of the favourite subjects of Japanese drama. Kabuki and puppet plays, historical novels, television series and films have repeatedly retold it, often portraying Mitsuhide either as a traitor or as a man driven to desperation. Its unanswered questions continue to inspire new theories and books every year.

Key people

• Oda Nobunaga (1534–1582): the warlord who had brought central Japan under his control.
• Akechi Mitsuhide (c. 1528–1582): the general who led the attack; his birth year is uncertain.
• Oda Nobutada (1557–1582): Nobunaga’s eldest son and heir, killed at Nijo Palace.
• Toyotomi Hideyoshi (1537–1598): the general who avenged Nobunaga and went on to unify Japan.
• Tokugawa Ieyasu (1543–1616): Nobunaga’s ally, who escaped from Sakai and later founded the Tokugawa shogunate.

Timeline

• 1582, April: The Takeda clan is destroyed.
• 1582, mid-June: Nobunaga arrives in Kyoto and lodges at Honno-ji.
• 1582, 20 June, evening: Mitsuhide’s army leaves Kameyama.
• 1582, 21 June, early morning: Honno-ji is attacked; Nobunaga dies. Nobutada dies at Nijo Palace.
• 1582, late June: Tokugawa Ieyasu escapes through Iga.
• 1582, 2 July: Hideyoshi defeats Mitsuhide at Yamazaki; Mitsuhide is killed.
• 1582, 16 July: The Kiyosu conference settles the Oda succession.
• 1590s: Honno-ji is rebuilt on a new site in Kyoto.

Why it matters

The Honno-ji Incident removed Japan’s most powerful ruler at the moment he seemed close to unifying the country. Its result was not the end of unification but a change of leader: Toyotomi Hideyoshi completed the task, and Tokugawa Ieyasu, who had narrowly escaped, eventually inherited it. Few events in Japanese history have inspired so many dramas, novels and theories.