Tensho Migo Rebellion (2/2)Tokugawa vs Uesugi vs Hojo! The conflict immediately after the Honnoji Incident

When Kagekatsu learned of the retreat, he immediately set out for battle in northern Shinano. In addition to occupying Kaizu Castle where Nagayoshi Mori had left and entering the castle, he also supported Ogasawara Tosetsusai, a member of the Shinano Shugoshi clan who had been hiding in the Uesugi family, and attacked Fukashi Castle, where Yoshimasa Kiso was, and drove out Yoshimasa. At this time, Masayuki Sanada became Kagekatsu's vassal and was active in mediating with the lords of castles on the way to Fukashi Castle.

[Shinano Province] Uesugi Kagekatsu vs Hojo family

While Uesugi Kagekatsu attacked Shinano, the Hojo family also invaded from the south in an attempt to make Shinano their own. Ujimasa's younger brother, Ujikuni Hojo, took Numata Castle in Ueno Province and built a castle in between to separate Numata Castle and Iwatoki Castle, where Masayuki was, causing Masayuki to suffer. In the end, on July 9th, only half a month after becoming a vassal to Uesugi, Masayuki transferred from the Uesugi family to the Hojo family.

After conquering most of Ueno Province, the Hojo family crossed the Usui Pass, gained support from the Shinano clan, and subdued Saku County. At that time, there was Yoda Nobaba of the Tokugawa side in Komoro Castle in Saku District, but he was attacked by the Hojo family and fled from Komoro Castle. Later, Yoshimasa Kiso, who was driven away by the Uesugi family, also joined the Hojo army.

Uesugi's army moving south and Hojo's army moving northwest. The two sides will face off on July 14th at the Chikuma River in Kawanakajima.

I thought it would be a decisive battle, but Tokugawa Ieyasu came here and made his presence felt. They gradually invaded Shinano Province from the south and approached the territory acquired by the Hojo family. Hojo Ujinao, who chose to confront Ieyasu, whose territory was close to his own, decided to make peace with the Uesugi army, fearing a pincer attack.

On the other hand, Kagekatsu Uesugi attacked Shinano immediately after Shigeie Niideda's rebellion. There is no telling when the battle with Shigeie, which calmed down after the Honnoji Incident, will flare up again. I would like to settle things with Shigeie as soon as possible and calm down my territory.

As these two parties agreed, a peace agreement was reached on July 29th. As a result of the peace agreement, the Uesugi family took possession of four counties in northern Shinano and decided not to send troops south of Kawanakajima. The Hojo family, no longer attacked from behind, began a battle with Ieyasu to gain control of Kai Province.

[Shinano/Kai Province] Tokugawa Ieyasu vs Hojo family

Now, I have not talked about Tokugawa Ieyasu so far, but how did Ieyasu become involved in the Tensho-Migo War after the Honnoji Incident?

When the Honnoji Incident occurred, Ieyasu was touring Sakai (Osaka) with a small number of his retainers, including Tadatsugu Sakai, Yasumasa Sakakibara, Tadakatsu Honda, and Naomasa Ii. Ieyasu received the news on the same day as the Honnoji Incident, and because there was a possibility that Mitsuhide would attempt to kill him, he hurriedly set off to return to his territory, Mikawa Province (Shizuoka Prefecture). Passing through Iga, they crossed the sea and arrived in Mikawa Province on June 4th (Kami-kun Iga Crossing). Along with the preparations for subjugating Mitsuhide, preparations will also begin for the capture of Kai and Shinano, which have become vacant. On June 10, he sent a messenger to Hidetaka Kawajiri of Kai Province to return to Mino.

Ieyasu departed on June 14th leading the Mitsuhide subjugation force, but the next day he heard of Mitsuhide's death and returned to Hamamatsu Castle on the 21st after confirming the truth. After that, Ieyasu began to focus on conquering Kai and Shinano provinces in earnest.

The first thing Ieyasu did was to incorporate people from Kai and Shinano provinces. In addition to recruiting local powerful people to his side, he also incorporated former Takeda family vassals such as Yoda Nobaba, who he had hidden during the Koshu conquest, into his army. On the other hand, he left the pacification of Minami-Shinano to Tadatsugu Sakai and Nobumasa Okudaira, and entered Kofu Castle on July 9.

Afterwards, he tried to persuade Yoritada Suwa of Takashima Castle to take over Suwa District, but failed. Furthermore, at Fukashi Castle, Sadayoshi Ogasawara defected to the Hojo clan due to conflict with Tadatsugu Sakai and Nobumasa Okudaira, and the invasion of Shinano was slow to progress.

Meanwhile, the Hojo army began moving south toward Kai, so Ieyasu entered Shinfu Castle in Kai Province as a countermeasure against Hojo. On the other hand, the Hojo army led by Ujinao Hojo enters Wakamiko Castle. The two sides faced each other for 80 days.

Furthermore, the Hojo army planned to move separate troops from Suruga Province and Musashi Province to attack Ieyasu from behind. On August 12th, Hojo Ujitada and Tokugawa forces Torii Mototada and Hiraiwa Shinkichi will fight at Kurokoma in Kai Province. Hojo 10,000 vs. Tokugawa 2000 seemed to be an advantage for the Hojo army, but when it turned out, the Tokugawa army won. After this battle, some military commanders began to abandon the Hojo army. Ieyasu succeeded in getting Yoshimasa Kiso, who was from the Hojo side, to his side. In September, they succeeded in attracting Masayuki Sanada.

Key man of war, Masayuki Sanada

In fact, the Tokugawa army was suffering from a lack of supplies during the invasion of Shinano Province, and was trying to obtain supplies by recruiting Masayuki Sanada to their side. It appears that a great deal of effort was put into soliciting him, such as by directly delivering a letter from Ieyasu and having someone related to Masayuki take care of it for him. Ieyasu issued a letter of address to Masayuki specifying that in addition to the territory he currently controlled, he would be given 2,000 kanbun of land in Minowa and Kai provinces in Ueno province, and Suwa district in Shinano province.

Masayuki had originally planned to acquire Numata Castle from the Hojo family, but the Hojo family openly declared that ``Numata Castle belonged to the Hojo,'' which caused him to mistrust the Hojo family. Numata Castle is located in Nishi-Ueno, and is a cliff castle built on a plateau surrounded by three rivers. It is an important military base connecting Echigo, northern Kanto, and northern Shinano, and is a place that Masayuki would definitely like to see.

In this way, Masayuki defected to the Tokugawa family and provided military supplies to Yoda Nobaba, who was in Shinano Province. Furthermore, he regained Numata Castle from the Hojo family. The Hojo family tried to take back Numata Castle, but they were unable to do so due to the fierce resistance of the Sanada army.

Furthermore, in October, Yoda Nobaba attacked Komoro Castle in Shinano Province and drove out Daidoji Masashige, and also captured Uchiyama Castle in Saku District. In addition, they will occupy Masayuki and Usui Pass. As a result of these movements, the Hojo army was cut off from its supply route. Fukashi Castle was also recaptured by the Tokugawa army, and the Hojo family found themselves in a predicament in Shinano.

Despite trying to break out of the war, Yoshishige Satake of Hitachi Province (Ibaraki Prefecture) became active in the Kanto region and attacked Tatebayashi Castle on the Hojo side. Feeling a growing sense of crisis, Ujinao decides to make peace.

Against this background, Hojo and Tokugawa made peace on October 29, with Oda Nobunaga's second son, Oda Nobuo, acting as a mediator. As a result, it was decided that Kai Province and Shinano Province would be ruled by the Tokugawa family. Ueno Province was left to the Hojo family, and Numata Castle was returned to the Hojo clan from Masayuki Sanada. Furthermore, as a condition of peace, Ujinao and Ieyasu's second daughter, Princess, were married.

This peace led to a conflict between the Sanada and Tokugawa families. In the first place, when the Tokugawa clan descended, Numata Castle was supposed to belong to the Sanada family. For this reason, Masayuki refused to hand over Numata Castle. He broke away from the Tokugawa family and became subordinate to the Uesugi family. This led to the first Battle of Ueda Castle in 1585, and the conflict between the two families continued from then on.