, also known as Uesugi Ujinori, was the chief advisor to Ashikaga Mochiuji

Ashikaga Mochiuji

Ashikaga Mochiuji was the Kamakura-fu's fourth Kantō kubō during the Sengoku period in Japan. During his long and troubled rule the relationship between the west and the east of the country reached an all-time low. Kamakura was finally attacked by shogun Ashikaga Yoshinori and retaken by force...

, an enemy of the Ashikaga shogunate

Ashikaga shogunate

The , also known as the , was a Japanese feudal military regime, ruled by the shoguns of the Ashikaga clan.This period is also known as the Muromachi period and gets its name from Muromachi Street of Kyoto where the third shogun Ashikaga Yoshimitsu established his residence...

 in feudal Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. When he was rebuked by Mochiuji in 1415, and forced to resign, Zenshū organized a rebellion.

Zenshū received aid for his rebellion from nearly half the daimyo

Daimyo

is a generic term referring to the powerful territorial lords in pre-modern Japan who ruled most of the country from their vast, hereditary land holdings...

 in the northern and eastern provinces, and took Kamakura

Kamakura, Kanagawa

is a city located in Kanagawa Prefecture, Japan, about south-south-west of Tokyo. It used to be also called .Although Kamakura proper is today rather small, it is often described in history books as a former de facto capital of Japan as the seat of the Shogunate and of the Regency during the...

. Mochiuji was forced to flee the city. However, despite pursuing similar goals to those of the shogunate (bakufu), Zenshū was still rebelling against his lord, and so the bakufu had no choice but to send troops to stop him. In 1417, Zenshū and his allies found themselves surrounded. They fled to Kamakura's Tsurugaoka Hachiman-gū, where Zenshū committed seppuku

Seppuku

is a form of Japanese ritual suicide by disembowelment. Seppuku was originally reserved only for samurai. Part of the samurai bushido honor code, seppuku was either used voluntarily by samurai to die with honor rather than fall into the hands of their enemies , or as a form of capital punishment...

.

The rebellion did not end with Zenshū's death, however, and neither did Mochiuji's opposition to it. For more than five years, Mochiuji continued to attack Zenshū's allies, including the Oda clan

Oda clan

The was a family of Japanese daimyo who were to become an important political force in the unification of Japan in the mid-16th century. Though they had the climax of their fame under Oda Nobunaga and fell from the spotlight soon after, several branches of the family would continue on as daimyo...

, Takeda family

Takeda family

The ' was a famous clan of daimyō in Japan's late Heian Period to Sengoku period.The Takeda were descendants of Emperor Seiwa and are a branch of the Minamoto clan , by Minamoto no Yoshimitsu , brother to the Chinjufu-shogun Minamoto no Yoshiie...

, and nobles of Musashi Province

Musashi Province

was a province of Japan, which today comprises Tokyo Prefecture, most of Saitama Prefecture and part of Kanagawa Prefecture. It was sometimes called . The province encompassed Kawasaki and Yokohama...

. Anger towards Mochiuji and his office only continued to grow, until the bakufu took action to stop him in 1423.