The Tōhoku Sekigahara Campaign was a series of sieges fought in the northern part of the main island of Honshū between the Eastern and Western Armies. The battles took place before and during the Battle of Sekigahara, which happened on October 21, 1600. The battles were fought between the Uesugi clan, who sided with the Western Army and the Date and Mogami clans, who fought for the Eastern Army. There are four sieges that make up the entirety of the Tōhoku Sekigahara Campaign: Shiroishi, Hataya, Kaminoyama and Hasedō.

Before the Campaign

After Toyotomi Hideyoshi passed away in 1598, the country that had once known some peace was now facing the possibility of war yet again. Despite Hideyoshi giving five of the most powerful daimyō in Japan the authority to rule the country together until his son, Hideyori, came of age, it was obvious that some just wanted power for themselves. Tokugawa Ieyasu was one of these daimyō. His grabs for power were met with opposition from Ishida Mitsunari, who believed that Ieyasu was overstepping his responsibilities to keep the Toyotomi together. This began a divide within the country with daimyō choosing to side with either Ieyasu or Mitsunari.

One of these daimyō, who was also one of the regents placed in charge by Hideyoshi was Uesugi Kagekatsu.(1) The Uesugi was in an alliance with Mitsunari, which made Ieyasu distrustful of them to start off with, but problems arose when rumors began spreading that Kagekatsu was building up his domain for war. Furious, Ieyasu sent a letter, demanding that Kagekatsu come to the capital to explain himself. What Ieyasu got instead was a response written by one of Kagekatsu’s most loyal retainers, Naoe Kanetsugu, which has become known today as the Naoe-jo.(2)

This letter explained that the Uesugi were just building up their new domain of Aizu that was given to them by Hideyoshi just before his death and Kanetsugu explained that they would not be coming to the capital while the treasonous accusations still circulated. Kanetsugu called out Ieyasu for slander, and in return, Ieyasu declared war on the Uesugi. Ieyasu called upon an ally in the north, Date Masamune, to take care of the Uesugi while he made his way to face Mitsunari at the Battle of Sekigahara. Date Masamune and Mogami Yoshiaki made the first move by attacking Shiroishi Castle. This was the beginning of the Tōhoku Sekigahara Campaign.

The Siege of Shiroishi, 1600

Forces: Date-Mogami (Eastern) vs. Uesugi (Western)

Causalities: Unknown

Shiroishi Castle was the first siege in the Tōhoku Sekigahara Campaign. The castle laid just south of Sendai, the Date clan’s stronghold, and was held by a retainer of the Uesugi clan. Date Masamune made the first move against the Uesugi clan by gathering his forces and headed south to lay siege to Shiroishi Castle. The castle fell to the Eastern Army, prompting the Uesugi to rally their forces to attack the Date/Mogami alliance. Naoe Kanetsugu would be the leader of the Uesugi Army.(3)

The Siege of Hataya, 1600

Forces: Date-Mogami (Eastern) vs. Uesugi (Western)

Casualties: Unknown

Numbers: 300 (Eastern) vs. 20,000 (Western)

The next siege in the Tōhoku Sekigahara Campaign was the siege at Hataya Castle. Naoe Kanetsugu took an army of 20,000 from Yonezawa and began to advance towards Yamagata Castle, Mogami Yoshiaki’s castle. Naoe Kanetsugu had two armies fighting against the Date/Mogami alliance: his own of 20,000 and an army of 4,000 led by Honmura Chikamori who made his way to Kaminoyama Castle.(4)

The first stop on the advance led by Kanetsugu was at Hataya. Eguchi Gohei was the commander of Hataya and only had three hundred men with him there. During the defense, Gohei had a shinobi go into the Uesugi main camp and took the sashimon from a guard and placed it above the front gate of the castle, a strategy of psychological warfare. The strategy did not work, however, as the castle fell to the Uesugi.(5)

The Siege of Kaminoyama, 1600

Forces: Date-Mogami (Eastern) vs. Uesugi (Western)

Causalities: Unknown

While Naoe Kanetsugu was laying siege to Hataya Castle, Honmura Chikamori took his forces to Kaminoyama Castle. The castle was held by Satoni Minbu, a retainer of the Mogami clan. Little is known about what happened here, but what is known is that the castle fell to the Eastern Army at the cost of the death of Honmura Chikamori.(6)

The Siege of Hasedō, 1600

Forces: Date-Mogami (Eastern) vs. Uesugi (Western)

Causalities: 623 (Eastern) vs. 1,580 (Western)

Numbers: 10,000 (7,000 Mogami/3,000 Date) vs. 25,000-30,000

The siege of Hasedō Castle is the most famous battle of the whole Tōhoku Sekigahara Campaign and it is also the final siege in this campaign. The siege was the last stop for the Uesugi before Yamagata Castle, which was the main goal. Naoe Kanetsugu waited a couple of days for his second force to arrive before laying siege to Hasedō. They laid siege to the castle for fourteen days, but the castle still managed to hold its ground. The castle was finally relieved by Date’s forces, causing Naoe Kanetsugu to declare an all-out attack on Hasedō. Kasuga Mototada was the vanguard and he and his men charged the castle, but was forced to retreat due to arquebus fire. An army from the castle charge forth and then began attacking the retreating Uesugi force. This led to an almost full retreat of the Uesugi forces. A small force remained behind to continue laying siege to the castle, but the battle would be cut short.(7)

On November 5, 1600, a messenger from Yonezawa reported to Naoe Kanetsugu that the Western Army was defeated at Sekigahara and Ishida Mitsunari had been captured. Kanetsugu was ordered to withdraw and return to Yonezawa.(8) Naoe Kanetsugu called a full retreat with Maeda Keiji protecting the retreating army. Date Masamune got the same information around the same time and pursued the retreating army all the way back. After arriving, the news of the defeat was confirmed: their efforts had been for naught.(9)

The Aftermath

The Uesugi clan fared well considering their situation after the campaign had ended. While most clans were destroyed or placed in exile, the Uesugi clan unconditionally surrendered and pledged their allegiance to Ieyasu. The Uesugi ended up changing their name to Shigemitsu. Their lands were reduced to just the fief of Yonezawa with their income dropping to 60,000 koku from their 1.2 million koku. They were required to prove their worth, fighting against former allies at Ōsaka Castle in 1614.

The Date clan were rewarded extremely for their service. They were given lands that were promised by Ieyasu to produce a million koku, however, it only managed to produce 640,000 koku, most going to the city of Edo to feed its people. Date Masamune relocated to Sendai in 1604 and turned it into a prosperous city. He would also fight against the last of the Toyotomi during the siege at Ōsaka Castle.(10)

Peace came to the land once again, and both clans remained prominent in Japanese history. For the Date, it was because of the power that they held after the war. In the case of the Uesugi, the credit for their survival goes to Naoe Kanetsugu, who was the driving force behind their success.

Sources

1. Bryant, Anthony J. Sekigahara 1600: The final struggle for power (2009), p. 34
2. See article on Naoe Kanetsugu
3. Turnbull, Stephen. The Samurai Sourcebook (2000), p. 251
4. Turnbull, Stephen. The Samurai Sourcebook (2000), p. 251
5. Turnbull, Stephen. The Samurai Sourcebook (2000), p. 168
6. Turnbull, Stephen. The Samurai Sourcebook (2000), p. 251
7. Turnbull, Stephen. The Samurai Sourcebook (2000), pp. 251-252
8. Bryant, Anthony J. Sekigahara 1600: The final struggle for power (2009), p. 92
9. Turnbull, Stephen. The Samurai Sourcebook (2000), p. 252
10. “Date Masamune”, https://en.wikipedia.org/wiki/Date_Masamune, last visited 8/30/2021

Data on casualties during these sieges come from their respective Wikipedia articles:

“Siege of Shiroishi”, https://en.wikipedia.org/wiki/Siege_of_Shiroishi, last visited 8/30/2021

“Siege of Hataya”, https://en.wikipedia.org/wiki/Siege_of_Hataya, last visited 8/30/2021

“Siege of Kaminoyama”, https://en.wikipedia.org/wiki/Siege_of_Kaminoyama, last visited 8/30/2021

“Siege of Hasedō”, https://en.wikipedia.org/wiki/Siege_of_Hasedō, last visited 8/30/2021