Tokugawa Ieyasu’s Ambition to Unite Japan

Have you ever thought about the modern Japanese emperors were not the first time being powerless public figures? Well, the emperors from medieval Japan were treated the same by society. From 1192 to 1868, Japan was ruled under three different feudal governments called shogunates which were led by shoguns. Shogun was the commander-in-chief during feudal Japan who held all the military power in his hands and was the real ruler of the country over the emperor and the royal family who resided in Kyoto. However, during the Ashikaga shogunate, the second shogunate, constant civil wars between daimyos, feudal lords, which weakened the shogunate and the daimyos lost their loyalty. In 1467, the three leading daimyos “provoked the opening hostilities of the Onin war in Kyoto,” which the civil war then tangled all daimyos in provinces into an age of warring states that lasted from 1467-1603. Japanese historians called it the Sengoku period.

Toward the end of the Sengoku period, three daimyos had risen to power, they were Oda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu, and they were called the three great unifiers of Japan. Although Ieyasu only came to power in 1598, he did not suddenly want to be the shogun to rule Japan; instead, he had the ambition to take over since he became a loyal retainer of Nobunaga, then transferred his loyalty to Hideyoshi after Nobunaga’s death, and finally rebelled against the Toyotomi clan to conquer all the daimyos who opposed him which united Japan and ended the Sengoku period.

Ieyasu made an important military alliance with Nobunaga, who was one of the most powerful daimyos in 1562, which marked the beginning of Ieyasu’s rise to power as a daimyo when he was fighting along with Nobunaga and received the Suruga province as a reward from Nobunaga. Nobunaga expanded the Oda clan’s influence outside of the Owari province, the western half of today’s Aichi Prefecture, as he conquered more and more daimyos who opposed him. By the end of Nobunaga’s conquest, the Oda clan controlled all of central Japan and planned to expand toward the west. Ieyasu saw the potential of uniting Japan in Nobunaga, whom Ieyasu followed with absolute loyalty. For instance, Ieyasu’s son and wife were found suspicious of treason, then Nobunaga demanded Ieyasu to kill them shortly afterward. Not only did Ieyasu not defend for his son and wife, but he also forced them to commit suicide without hesitation. Ieyasu reacted to this incident with the words: “I bear Nobunaga no rancor. . .. As long as I am locked in conflict with [my enemy, Takeda Katsuyori] and depend on Nobunaga to back me up, I cannot very well defy Nobunaga. It cannot be helped”. Simply put, Ieyasu’s dedication to defeat his enemy Takeda Katsuyori and gain more territorial control with the help of Nobunaga had overwhelmed his paternal bond with his son and wife, who were killed without clear evidence of treason. Since Nobunaga was the most powerful daimyo at the time, even if Ieyasu wanted revenge for his family, Nobunaga would have crushed Ieyasu’s army and the Tokugawa clan fairly quickly, and Ieyasu’s dream of uniting Japan would vanish. Therefore, for Ieyasu to preserve his glory and power as a daimyo, his only choice was to follow Nobunaga’s intolerable demand and act as a loyal retainer despite Nobunaga’s ruthless leadership and control over his subjects. However, Nobunaga’s glory did not last when one of his retainers Akechi Mitsuhide rebelled against Nobunaga in 1582 and forced him to suicide at Honnoji, Kyoto, also known as the Honnoji Incident. Ieyasu’s army was not powerful enough to take over Japan by the time of Nobunaga’s death, so he submitted himself to Toyotomi Hideyoshi, the successor of the Oda clan, and continue to gain political and military power while no one was trying to stop him.

After Nobunaga’s death, Hideyoshi took over his power and followers, including Ieyasu, then Hideyoshi finished Nobunaga’s work of uniting Japan by finish conquering the rest of Honshu, Shikoku, and Kyushu in 1590. After that, Hideyoshi tried to reform the society after decades of wars and passed laws that unintentionally helped Ieyasu to become a dominant daimyo as Ieyasu was strategically staying out of Hideyoshi’s domain to prevent conflicts. Ieyasu regarded Hideyoshi as one of his formidable opponents after Nobunaga, and Ieyasu tried to avoid any conflicts with Hideyoshi by being a loyal retainer of the Toyotomi clan (Turnbell 53). For instance, Hideyoshi redistributed daimyos into different provinces throughout Japan, and he appointed the daimyos he trusted to the provinces in the Kansai region surrounding Osaka and sent Ieyasu to farther east in the Kanto region. Also, Ieyasu agreed to exchange his home province Mikawa for the Kanto provinces in the eastern Honshu with Hideyoshi since Mikawa was close to Osaka. Kanto was far away from Hideyoshi’s home province Osaka and Hideyoshi though he would be safe from Ieyasu’s potential threat. Ieyasu moved his capital from the Mikawa province to the eastern Honshu and established his new capital in Edo, modern-day Tokyo. Not only did Ieyasu’s migration prevent him from having a direct conflict of interest with Hideyoshi, but the Kanto plain areas and the Tokyo Bay also provided resources for the Tokugawa clan to flourish. Although Ieyasu was forced to leave Mikasa, separating himself from Hideyoshi was his only way to strengthen his army without being suspicious of treason then get eliminated by Hideyoshi’s superior army (Turnbell 53). Besides, moving Ieyasu to the east had benefited him, and Hideyoshi’s policies that tried to stabilize the society also helped Ieyasu to be a threat to Hideyoshi in later times. For instance, Hideyoshi enacted the edict of Katana Kari (Sword Hunting) to remove swords from civilians and to prevent his newly united empire from falling into a warring state again since one of the main causes of the Sengoku period was people from the lower hierarchy were having too much power and got out of control. The edict had stated all farmers in the country were forbidden to possess any weapons, or they would be brought to trial. Not only that, if samurais failed to enforce the law and punish the offenders, they would lose the rights and profits from the farms. The edict also stated if farmers focus exclusively on farming and give up their temptation to rebel against the state, their decedents will prosper on the land they farmed and would bring peace, happiness, and security to all people. Furthermore, with the enactment of Hideyoshi’s Sword Hunting, Ieyasu did not need to worry about the local farmers rebelling him as the new leader of the Kanto region because Kanto used to be controlled by Ieyasu’s enemies. Since Hideyoshi had removed his biggest threat Ieyasu from his eyesight, he launched campaigns to conquer Korea then Ming China when Ieyasu strategically remained in Kanto and did not lose his military strength in Korea. While Ieyasu was strengthening his army without any major disturbance, Hideyoshi’s army was getting destroyed by Korea with the help of China, then Hideyoshi died soon after. Hideyoshi’s failure drastically weakened one of his most accomplished generals, Ishida Mitsunari, who played a crucial role in the Toyotomi clan when Hideyoshi died (Turnbell 54). Ieyasu saw the fall of Hideyoshi and the Toyotomi clan as his best opportunity to rise and steal what his former lords had accomplished then conquer all of Japan for himself.

On Hideyoshi’s yuigon, or will, he appointed five of his trusted retainers, including Tokugawa Ieyasu, Maeda Toshiie, Ukita Hideie, Uesugi Kagekatsu, and Mori Terumoto as the Council of Five Elders to assist Hideyoshi’s five-years-old son Hideyori to rule Japan before he died in 1598 (Yuigon Oboegakian). However, Ieyasu often broke the alliance between the Five Elders, then rebelled against the Toyotomi clan and took the rulership from Hideyori, which initiated the decisive battle of the Sengoku period in 1600, the Battle of Sekigahara. Council of Five Elders vanished within two years of establishment, and Ishida Mitsunari, who took over the Toyotomi clan, led the Western Army from Osaka to fight against the Eastern Army of Ieyasu from Edo at Sekigahara in today’s Gifu prefecture. After Ieyasu defeated Mitsunari, he received the title of shogun from the emperor and established the third and last feudal government in Japan in 1603, the Tokugawa shogunate. Ieyasu’s betrayal to Hideyoshi who he had allied since the Nobunaga era had once again shown his ambition to rule Japan had overridden his human emotions. Ieyasu abolished his years of kinship with Hideyoshi once Hideyoshi died and he valued his military success over everything else. However, Ieyasu was unsatisfied with his title of shogun and rulership of Japan. Ieyasu wanted to minimize the risk of getting betrayed as he did to Hideyoshi, then he eliminated the Toyotomi clan completely after the Siege of Osaka in 1615 (Trunbell 52). As a result, there were no major threats to the Tokugawa shogunate until the ruling power was finally returned to the emperor during the Meiji Ishin in the 1800s which abolished the feudal system. After almost 150 years of civil wars between daimyos, Japan was finally united by the joined effort of Oda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu even though Ieyasu purposely stayed behind-the-scene to take over Japan when the former two died early.

Even the great and ruthless daimyo Oda Nobunaga had lost to no one but his retainer, for Ieyasu to unite Japan during the era of violence and betrayal, he must unitize his characteristic of careful, bold, and cunning to make suitable alliances at the right time that would benefit his rise to power. Also, if Ieyasu did not take control of Japan when Hideyoshi died, the society might fall into chaos and Japan might become a warring state again. Although not everyone agrees with how Ieyasu came to power without conquering most of his enemies by himself like his former lords Nobunaga and Hideyoshi, Ieyasu’s establishment of the Tokugawa shogunate was very important for laying a strong foundation for Japan to become a dominant empire in East Asia for centuries.

Works Cited

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