The Kyōtoku Incident was a long series of skirmishes and conflicts fought for control of the Kantō region

Kanto region

The is a geographical area of Honshu, the largest island of Japan. The region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba, and Kanagawa. Within its boundaries, slightly more than 40 percent of the land area is the Kantō Plain....

 of 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...

 in the 15th century. The conflict began in 1454 with the assassination of Uesugi Noritada by Kantō kubō

Kanto kubo

was a title equivalent to shogun assumed by Ashikaga Motouji after his nomination to Kantō kanrei, or deputy shogun for the Kamakura-fu, in 1349. Motouji transferred his original title to the Uesugi family, which had previously held the hereditary title of , and would thereafter provide the Kantō...

Ashikaga Shigeuji

Ashikaga Shigeuji

was a Muromachi period warrior and the Kamakura-fu's fifth and last Kantō Kubō . Fourth son of fourth Kubō Ashikaga Mochiuji, he succeeded his father only in 1449, a full decade after his death by seppuku. His childhood name was...

. The Ashikaga

Ashikaga clan

The ' was a prominent Japanese samurai clan which established the Muromachi shogunate and ruled Japan from roughly 1336 to 1573.The Ashikaga were descended from a branch of the Minamoto clan, deriving originally from the town of Ashikaga in Shimotsuke province .For about a century the clan was...

, Uesugi

Uesugi clan

The was a Japanese samurai clan, descended from the Fujiwara clan and particularly notable for their power in the Muromachi and Sengoku periods ....

, and other clans then leapt to battle, either defending or assaulting Shigeuji. The chaos ended in 1482, when a peace was negotiated.

Chronology

Ashikaga Shigeuji was appointed to the post of Kantō kubō (Shogun's deputy in the Kantō) in 1449, the first Ashikaga to hold the post since his father's death ten years earlier. At that point, in 1439, Uesugi Norizane

Uesugi Norizane

Uesugi Norizane was a Japanese samurai of the Uesugi clan who held a number of high government posts during the Muromachi period....

 had seized power for his clan. Ten years later, the Uesugi remained powerful in the Kantō; in 1454, Shigeuji arranged to have his deputy, Uesugi Noritada, killed.

This was taken as rebellion against the shogunate, and armed conflict quickly broke out. The Uesugi clan mobilized to attack Shigeuji, and Imagawa Noritada, loyal to the shogunate, captured and burned 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...

, which was the center of the Kantō bureaucracy and Shigeuji's home. Shigeuji then fled the area, to Koga

Koga, Ibaraki

is a city located in Ibaraki, Japan.-Old City of Koga:The city has its origins in the Tokugawa period when a castle was built in the 16th century at the river crossing point and a town sprang up around it. The site of the castle is still visible near Koga 1st elementary school. The modern city was...

, in Shimotsuke province

Shimotsuke Province

is an old province of Japan in the area of Tochigi Prefecture in the Kanto region. It was sometimes called or .The ancient capital of the province was near the city of Tochigi, but in feudal times the main center of the province was near the modern capital, Utsunomiya.-History:Different parts of...

, and became known as the Koga kubō. The Uesugi called for the shogunate to send a new kubō to replace Shigeuji, and in 1459, the shogun's brother, Ashikaga Masatomo, arrived to take up that position. However, Shigeuji's supporters refused to acknowledge this, and maintained Shigeuji's rightful claim to the post. Masatomo set up his new home in Horigoe, in Izu province

Izu Province

was a province of Japan in the area of Shizuoka Prefecture. Izu bordered on Sagami and Suruga Provinces. Its abbreviated form name was .The mainland portion of Izu Province, comprising the Izu Peninsula is today the eastern portion of Shizuoka Prefecture and the Izu Islands are now part of...

. As the fighting continued, both claimed to be on the side of the shogunate; but both sides prevented one another from wielding true power, and so the Uesugi were once again in control of the region.

Due to their growing power and numbers, the Uesugi clan now split in three branches (Yamanouchi, Ōgigayatsu, and Inukake), named after the localities within the Kantō where they resided.

The Ōnin War

Onin War

The ' was a civil war that lasted 10 years during the Muromachi period in Japan. A dispute between Hosokawa Katsumoto and Yamana Sōzen escalated into a nationwide war involving the Ashikaga shogunate and a number of daimyo in many regions of Japan....

 broke out in Kyoto in 1467, signalling the end of the shogunate's real power and the beginning of the Sengoku period

Sengoku period

The or Warring States period in Japanese history was a time of social upheaval, political intrigue, and nearly constant military conflict that lasted roughly from the middle of the 15th century to the beginning of the 17th century. The name "Sengoku" was adopted by Japanese historians in reference...

, a period of chaos and war which would last 150 years. Fighting in the Kantō between the Ashikaga and Uesugi calmed for about ten years, resuming in 1477 and ending in 1482, with negotiations for peace.