Stories of the Japanese 01264 [Muromachi/Yoshimitsu Period] The Second Rebellion of Date Masamune and the Sasakawa Kubo

While the shogunate was struggling to suppress Ouchi Morimi, the Second Rebellion of Date Masamune was occurring simultaneously in Oshu.
April, Oei 9 (1402). Upon receiving reports that Date Masamune, who should have surrendered a year and a half earlier, had taken up arms again, Kanto Kanrei Uesugi Tomomune dispatched a suppression force led by his son, Ujinori (?-1417). This father-son pair, Tomomune and Ujinori, belonged to a branch of the Uesugi family classified as the "Inukake Uesugi clan."
Now, Uesugi Ujinori has made his first appearance. He might be better known by his Buddhist name, "Zenshu." Much later, he would become the figure who instigated the famous "Uesugi Zenshu Rebellion," which is even mentioned in textbooks.
In September, Uesugi Zenshu attacked Mutsu Akadate (Koori Town, Fukushima Prefecture), defeated Masamune, and forced him to surrender. The fallen Date Masamune fled to the remote Dewa Takahata Castle (Takahata Town, Yamagata Prefecture) and died in Oei 12 (1405). Although Masamune was ultimately defeated by the Kamakura-fu, he is considered the restorer of the Date family because, before turning against the Kamakura-fu, he had expanded his territory by defeating the Nagai clan and acquiring lands in Okitama (Yonezawa City, Yamagata Prefecture). It is said that the Date Masamune of the Sengoku period took the same name in honor of this Masamune from the early Muromachi period.
The Second Rebellion of Date Masamune was suppressed quite easily, but there is no record of Inamura Kubo Mitsusada playing an active role in this suppression. Because the Kamakura-fu directly commanded the suppression of the rebellion, the influence of the Inamura Kubo declined significantly.
Incidentally, let me introduce Ashikaga Mitsutada (1386–1440) of the Sasakawa Kubo here as well.
The second Kamakura Kubo, Ujimitsu, had five children. His eldest son, Mitsukane, became the third Kamakura Kubo, and his fourth son, Mitsusada, became the Inamura Kubo, but his second son, Mitsutada, was dispatched to Sasakawa (Koriyama City, Fukushima Prefecture) and was called the "Sasakawa Kubo." Oshu was to be governed through the cooperation of the Inamura Kubo and the Sasakawa Kubo.
It has been said that Date Masamune and Osaki Akimochi rebelled against both the Inamura and Sasakawa Kubos, but recent research suggests:
• The dispatch of Inamura Kubo Mitsusada was around Oei 6 (1399).
• The dispatch of Sasakawa Kubo Mitsutada was around Oei 21 (1414).
It is now believed that "the Sasakawa Kubo did not exist at the time Date Masamune rebelled." According to this new theory, the Inamura Kubo was dispatched by Mitsukane to govern Oshu, while the Sasakawa Kubo was, conversely, a hostile force dispatched by Uesugi Zenshu to oppose Mitsukane. In other words,
"Kamakura Kubo Ashikaga Mitsukane & Inamura Kubo Ashikaga Mitsusada VS Inukake Uesugi Zenshu & Sasakawa Kubo Ashikaga Mitsutada"
there was an axis of conflict as described above.
Come to think of it, the Inamura Palace, where the Inamura Kubo resided in Sukagawa City, Fukushima Prefecture, and Takase in Sasagawa, Asaka-machi, Koriyama City, Fukushima Prefecture, where the Sasakawa Kubo resided, are only 11 km apart, so there was no need to establish them separately. It seems appropriate to view them as having been in opposition.