The Kusuko Incident (薬子の変)

The Kusuko Incident is an incident that occurred in the early Heian period.

There was a confrontation between the Retired Emperor Heizei and Emperor Saga, but it resulted in the Retired Emperor Heizei's becoming a monk due to Emperor Saga's quick mobilization of soldiers. FUJIWARA no Kusuko, the Retired Emperor's concubine, and her elder brother FUJIWARA no Nakanari were punished.

Because it was thought that FUJIWARA no Kusuko and her elder brother had taken leading roles in this incident, it has usually been referred to as the 'the Kusuko Incident.'
However, some have concluded that this incident occurred because in the Daijo tenno (retired emperor) system under the Ritsuryo system sovereign power was divided, and the expression 'the Incident of the Retired Emperor Heizei' has been used in some high school textbooks since 2003.

Background
In 806, Emperor Kanmu died and the Crown Prince Ate acceded to the throne. He was Emperor Heizei. Emperor Heizei appointed his brother, Imperial Prince Kamino, as kotaitei (an emperor's brother who was appointed as his successor). It is said that this was the will of their father Emperor Kanmu, who believed a hereditary imperial succession would be difficult, considering Emperor Heizei's being in poor health and his children still being young. But there was an incessant string of disputes over the imperial succession inside the court, such as the emperor's brother by a different mother, Imperial Prince Iyo, being framed with the crime of plotting a rebellion and driven to death the next year.

When Emperor Heizei was stricken by disease in April, 809, he decided to abdicate the throne to keep out of harm's way because he thought the ghosts of Imperial Prince Sawara and Imperial Prince Iyo had caused his sickness.
Although FUJIWARA no Kusuko of the Handmaid's Office (Naishi no Tsukasa), who had been in the emperor's favor and extremely domineering, and her brother FUJIWARA no Nakanari opposed it tooth and nail, the emperor's will was so strong that he abdicated the throne on April 13 of the same year, and Imperial Prince Kamino acceded to the throne.(Emperor Saga)
Emperor Heizei's son Imperial Prince Takaoka was appointed as the Crown Prince.

In 810, the abdicated Emperor Heizei moved to the old capital of Heijo-kyo. Since Emperor Saga tried to change the system of kansatsushi (inspectors in charge of surveying the misery of the people) that had been established during Emperor Heizei's reign, it enraged the Retired Emperor Heizei and there occurred a conflict called nisho chotei (two Imperial Courts existing at the same time). Kusuko and Nakanari, who had been scheming to restore the Retired Emperor Heizei to the throne, greatly encouraged this conflict.

Emperor Saga established the office of Kurodo no to (Head Chamberlain) in March, and discontinued kansatsushi and restored Sangi (councillor) in June. This provoked the Retired Emperor Heizei.

The course of the incident

While the conflict between the two Imperial Courts existing at the same time was getting deeper and deeper, the Retired Emperor Heizei gave an imperial edict about discontinuing the Heian-kyo capital and moving the capital back to Heijo-kyo on September 6 (according to the old calendar). This was an unexpected event for Emperor Saga, and as a temporary measure, he appointed SAKANOUE no Tamuramaro, FUJIWARA no Fuyutsugu and KI no Taue as zogushi (palace construction officer). It is thought that Emperor Saga aimed to send people who he trusted as zogushi to try to dissuade the Retired Emperor Heizei. The news of the capital's relocation greatly disturbed the public.

Emperor Saga was determined to reject the relocation of the capital. On September 10 (according to the old calendar), Emperor Saga dispatched envoys, and tightened the local government offices and crossing points in Ise, Omi and Mino provinces. In addition, he captured Nakanari and confined him at uhyoe-fu (Right Division of Middle Palace Guards), and issued an Imperial edict that he would demote Nakanari, deprive Kusuko of her rank at the Imperial Court and made a proclamation announcing their wrongdoings. Emperor Saga promoted SAKANOUE no Tamuramaro, who was a zogushi, to Dainagon (chief councilor of state). FUJIWARA no Fuyutsugu was appointed as Shikibu no taifu (Master of the Ministry of Ceremonial), and KI no Taue was appointed as Owari no kami (the governor of Owari Province).

On September 11 (according to the old calendar), Emperor Saga sent a secret messenger to Heijo-kyo and summoned a few high-ranking officials. As FUJIWARA no Manatsu and FUNYA no Watamaro had returned to the capital that day, Watamaro, who was considered a supporter of the Retired Emperor Heizei, was incarcerated at saeji-fu (Left division of guards).

The Retired Emperor Heizei was infuriated by Emperor Saga's actions, and he made a firm decision that he himself would go to the eastern provinces and raise an army. Chunagon (vice-councilor of state) FUJIWARA no Kadonomaro and other retainers remonstrated with the Retired Emperor as much as they could, but he headed for the east by palanquin with Kusuko.

Emperor Saga, knowing how the Retired Emperor Heizei had responded, ordered SAKANOUE no Tamuramaro to prevent the Retired Emperor from heading for the east. On his departure, Tamuramaro entreated the emperor to release from confinement FUNYA no Watamaro, who had been a fellow soldier during the conquest of the Emishi (Japanese northerners), and Watamaro was set free and appointed as Sangi. Nakanari was shot and killed that night by an archer. This was one of the rare cases where a government of the Heian period executed someone based on ritsuryo, and after this, the death penalty was not used for about 350 years until the execution of MINAMOTO no Tameyoshi, which was carried out during the Hogen Disturbance in 1156.

When the party of the Retired Emperor Heizei and Kusuko proceeded up to Tamura, in Soekami County, Yamato Province, they realized that their opponent's military defense was so strong, that there was no chance for them to win and they could do nothing but go back return to the Heijo-kyo. On September 12 (according to the old calendar), the Retired Emperor Heizei went back to Heijo-kyo, shaved his head and became a monk, while Kusuko committed suicide by poisoning herself.

Measures taken

After the incident, Emperor Saga published an imperial edict stating that he would deal leniently with those involved. Imperial Prince Takaoka was deposed as the Crown Prince, and the emperor's brother Imperial Prince Otomo (who later became Emperor Junna) was appointed instead. In addition, at the time of Retired Emperor Heizei's death in 824, Emperor Junna pardoned those involved in the incident at the request of the Retired Emperor Saga, who had already abdicated the crown.