Chris Perry, Author

Tag: Daimyo Alliances

  • The Third Unifier – Tokugawa Ieyasu. Part Five.

    The Third Unifier – Tokugawa Ieyasu. Part Five.

    By 1584, two years had passed since the Honnoji Incident and the death of Oda Nobunaga. His eldest son, Nobutada, had died alongside him at Honnoji, leaving several younger sons as potential successors. The problem was that none of these sons had much in the way of military resources with which to stake their claim, and they quickly formed alliances, or else became puppets of Nobunaga’s more powerful retainers, most notably Toyotomi Hideyoshi (still going by Hashiba at this time) and Shibata Katsuie.

    Hideyoshi carries Sanboshi during the Kiyosu Conference.

    In the immediate aftermath of Honnoji, a conference was held at Kiyosu Castle to decide which son would inherit his father’s lands. In the event, Hideyoshi used his influence to ensure that Nobunaga’s grandson, the three-year-old Hidenobu (also called Sanboshi), would be named as the new head of the Oda Clan, whilst Nobunaga’s territories were divided up between his remaining sons and most powerful retainers.

    It will come as no surprise that Nobunaga’s surviving adult sons were not thrilled about this, and it wasn’t long before rival camps were forming around one son or another. Initially, despite his earlier support of Sanboshi, Hideyoshi decided to back Nobunaga’s second son, Oda Nobuo, whilst Katsuie supported the third, Nobutaka.

    Oda Nobuo (left) and Oda Nobutaka, brothers, but rivals for their father’s position.

    Despite nominally supporting one Oda heir or the other, in reality, the rivalry was between Hideyoshi and Katsuie, and tensions rose sharply until the Battle of Shizugatake in June 1583. There, Hideyoshi won a decisive victory, and shortly afterwards, Katsuie and Nobutaka committed suicide, removing a serious obstacle on Hideyoshi’s road to power.

    Despite being on the ‘winning’ side, it wasn’t long before Oda Nobuo fell out with Hideyoshi, and in early 1584, he went looking for support. It’s at this point that Tokugawa Ieyasu reenters the story. Despite trying to stay on good terms with Hideyoshi, sending him congratulatory gifts after his victory at Shizugatake, for example, it was becoming obvious that Ieyasu was too powerful for Hideyoshi to simply leave alone.

    A 19th-century depiction of the Battle of Shizugatake

    The flashpoint came in March 1584, when Nobuo had a retainer who had been colluding with Hideyoshi executed. Using this pretext, Hideyoshi raised an army and marched on Nobuo, who appealed to Ieyasu for help. Ieyasu obliged and dispatched forces into Nobuo’s home province of Owari.

    What followed was what history records as the Battle of Komaki-Nagakute, which is misleading because it was actually a series of battles, only two of which took place anywhere near the eponymous locations. The momentum of the campaign swung back and forth throughout the spring and summer. Despite a considerable advantage in resources, Hideyoshi was unable to bring them to bear, resulting in a stalemate.

    An 18th-century depiction of the Battle of Komaki-Nagakute. Despite the name, it was actually a series of battles fought across central Japan.

    With success on the battlefield impossible, both sides sought diplomatic support from other clans, with Ieyasu reaching out to the Hojo and Chosokabe, whilst Hideyoshi gained the support of the Uesugi, Mori, and Satake. Even with these allies, the stalemate persisted, and the only option was to negotiate, and both sides sat down to talk in November.

    Though he had not achieved a military victory, the negotiations favoured Hideyoshi; he forced Nobuo to submit and cede several territories, whilst those who had supported Ieyasu found themselves either isolated or also forced to submit to Hideyoshi. Ieyasu himself retained his territories and arranged for his son, Hideyasu, to be adopted by Hideyoshi, though only sources favourable to the Tokugawa call it an adoption; Hideyoshi’s partisans describe Hideyasu as a hostage.

    Ieyasu’s son, Hideyasu. Whether he was an adopted son or a hostage depends on who you ask.

    The fact that Ieyasu had been able to force a stalemate against heavy odds is a noteworthy military achievement in itself, but it is made all the more remarkable by the fact that, throughout 1583-85, his territories had been subject to extraordinary rainfalls, which had led to flooding and the consequent devastation to infrastructure and food supplies.

    The Battle of Komaki-Nagakute could not be considered a ‘victory’ for either side, but Hideyoshi was clearly in the ascendancy, and Ieyasu’s resources had been strained to the brink by years of flood, famine, and war. Then, in 1586, the massive Tensho Earthquake struck, causing catastrophic damage across central Japan, striking both sides’ lands equally. Though his superior resources meant that Hideyoshi was probably better positioned to recover, he had bigger plans. Instead of attempting to crush Ieyasu a second time, he tried a different tack.

    The theorised intensity scale of the 1586 Tensho Earthquake.
    As6022014 – 宇佐美龍夫 『最新版 日本被害地震総覧 416‐2001』 , Lincun(2010)ファイル:地図 令制国 和泉国.svg, CC 表示-継承 3.0, https://commons.wikimedia.org/w/index.php?curid=18458686による

    Using Oda Nobuo as an intermediary, Hideyoshi attempted to convince Ieyasu to submit. Initially refusing, Ieyasu was finally convinced by an offer of marriage to Hideyoshi’s younger sister, Lady Asahi. Some sources suggest that Hideyoshi forced his sister to divorce her husband so the marriage could take place, whilst others suggest she was already divorced, or else her husband was dead. Either way, given that Lady Asahi was already in her 40s by the time the marriage took place, it was clearly a match made for political rather than dynastic reasons.

    A marriage like that may seem strange to our modern eyes, but it was generally seen as a politically savvy move, as it bound Ieyasu and Hideyoshi together as family. Shortly after the wedding, Ieyasu travelled to Osaka and formally submitted to Hideyoshi as his vassal and brother-in-law. Later Tokugawa sources suggest that on the night of his arrival in Osaka, Ieyasu was secretly visited by a nervous Hideyoshi, who was still unsure whether he truly meant to submit. The meeting is probably apocryphal, but Ieyasu certainly swore loyalty to Hideyoshi in an elaborate ceremony shortly afterwards.

    Lady Asahi, whose marriage to Ieyasu bound him and her elder brother, Hideyoshi, together. The fact that she was around 44 years old when they married was no obstacle.

    Later in 1586, Ieyasu moved his base to Sunpu, which was more central to his domains and better positioned to monitor peace in the Kanto region on Hideyoshi’s behalf. For the next few years, Ieyasu proved himself a loyal retainer. In 1590, when tensions between the Hojo and Hideyoshi began to rise, he attempted to act as a mediator, since he was father-in-law to Hojo Ujinao.

    Ieyasu’s diplomatic efforts bore some fruit, with the Hojo sending Ujinao’s uncle, Ujinori, to Kyoto to negotiate with Hideyoshi. However, Ujinao himself refused to come, and Hideyoshi was determined to either force the Hojo to submit or be destroyed. Later scholars suggest that Ieyasu’s position with the Hojo might have been deliberately undermined by rumours that he stood to benefit from their defeat, as he had been promised the eight provinces of the Kanto in exchange for the five he currently controlled, in the event of the Hojo being removed.

    The situation just before the Odawara Campaign. Ieyasu stood to gain control of the territory of the Hojo (green) in the event of their defeat, a fact that may have put a damper on previously good Tokugawa-Hojo relations.
    By Alvin Lee – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=39214209

    Ieyasu denied the rumours, and their exact impact on negotiations is controversial, but Tokugawa forces served Hideyoshi in the vanguard of what became known as the Odawara Campaign that saw the Hojo decisively defeated, and Ieyasu received the eight Kanto provinces as the rumours had suggested he would.

    Precisely why Hideyoshi offered these provinces to Ieyasu is still debated. It was certainly true that Ieyasu was in no position to refuse the offer, and taking possession of these new lands effectively doubled his income, at least on paper. On the other hand, the provinces had been Hojo territory for generations, and the local lords would prove difficult to control, not to mention the damage caused by the recent campaign.

    Edo Castle as it appeared in the 19th Century. The site was underdeveloped when Ieyasu arrived in 1590, but it would eventually grow to become the centre of his dynasty’s power.

    Some suggest that Hideyoshi genuinely believed in Ieyasu’s abilities to bring the region under control. Others conclude that his real intention was to separate Ieyasu from his power base in Mikawa. Either way, it would prove a fateful decision, perhaps best exemplified by the fact that Ieyasu’s chosen base, Edo Castle, is the site of the Imperial Palace in modern Tokyo.

    Sources
    https://ja.wikipedia.org/wiki/%E5%BE%B3%E5%B7%9D%E5%AE%B6%E5%BA%B7
    https://ja.wikipedia.org/wiki/%E6%B1%9F%E6%88%B8%E5%9F%8E
    https://ja.wikipedia.org/wiki/%E5%B0%8F%E7%89%A7%E3%83%BB%E9%95%B7%E4%B9%85%E6%89%8B%E3%81%AE%E6%88%A6%E3%81%84
    https://ja.wikipedia.org/wiki/%E7%B9%94%E7%94%B0%E7%A7%80%E4%BF%A1
    https://ja.wikipedia.org/wiki/%E7%B9%94%E7%94%B0%E4%BF%A1%E5%AD%9D
    https://ja.wikipedia.org/wiki/%E7%B9%94%E7%94%B0%E4%BF%A1%E5%BF%A0
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    https://ja.wikipedia.org/wiki/%E7%B9%94%E7%94%B0%E4%BF%A1%E9%95%B7
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    https://ja.wikipedia.org/wiki/%E6%9C%9D%E6%97%A5%E5%A7%AB

  • The Third Unifier – Tokugawa Ieyasu. Part Two.

    The Third Unifier – Tokugawa Ieyasu. Part Two.

    The Battle of Okehazama in 1560 saw Tokugawa Ieyasu’s masters, the Imagawa, dealt a serious blow at the hands of Oda Nobunaga. In the aftermath, Ieyasu began asserting his independence, and in 1562, the so-called “Kiyosu Alliance” between Ieyasu and Nobunaga was formalised.

    The mon of the Tokugawa.
    百楽兎 – 投稿者自身による著作物, CC 表示-継承 3.0, https://commons.wikimedia.org/w/index.php?curid=1056853による

    The Imagawa, however, were down, but not out, and Ieyasu’s position was far from secure, despite his new alliance. In 1563, the “Mikawa Ikko-Ikki” Rebellion broke out, and in early 1564, when the Imagawa announced their intention to crush Ieyasu, several of his vassals in Mikawa switched sides, joining the Ikko-Ikki or else rising against Ieyasu in anticipation of an Imagawa attack.

    The name “Ikko-Ikki” suggests that the uprising was similar to other religiously motivated risings that occurred throughout Japan during this period. Indeed, the focal point seems to have been several temples in Mikawa; however, some scholars now suggest that the uprising was motivated more by economic reasons, and some even go so far as to say that Ieyasu may have provoked the rising, or at least took advantage of it to cement his control of Mikawa Province.

    A later depiction of the Battle of Azukizaka. Ieyasu is the figure on the white horse on the right.

    While it’s impossible to know for sure, Ieyasu did much to boost his own reputation in putting down the rebellion. At the Battle of Azukizaka (sometimes called the Battle of Batogahara) in January 1564, Ieyasu led his forces in crushing the rebels, despite ferocious fighting. The story goes that Ieyasu charged the enemy fearlessly, and came under heavy gunfire, with several rounds penetrating his armour, but leaving him uninjured, inspiring his men, and leading some rebels to switch sides.

    In the aftermath, Ieyasu banned the Jodo Shinshu sect of Buddhism in Mikawa, only to lift the ban in 1567, just a few years later, lending credence to the argument that the fighting had never been about religious issues but about political control of the province.

    The Honshuji Temple, one of the focal points of the rebellion, as it appears today.

    Before 1566, Ieyasu’s family name was Matsudaira, but around this time, he petitioned the Emperor to change it to Tokugawa. The exact reasons for this are related to the complex (and often impenetrable) genealogies of the Minamoto and Fujiwara Clans, from whom Ieyasu claimed descent. You may remember that Minamoto and Fujiwara were the names of two of Japan’s most ancient and illustrious families, and it was a big deal to claim descent from them.

    This would become much more important later, as only a member of the Minamoto could become Shogun (technically), but that was still decades in the future. At the time, the name change was probably more closely associated with prestige and a desire to assert independence from the Imagawa, with a new name symbolising a new era for the clan.

    Takeda Shingen.

    In 1567, Ieyasu further strengthened his alliance with Nobunaga by marrying his eldest son to Nobunaga’s daughter. However, they were both just nine years old at the time, so the marriage was a political rather than conjugal union. The next year, Ieyasu dispatched forces to support Nobunaga’s march on Kyoto, and in December, he made an alliance with Takeda Shingen and launched a joint invasion of Imagawa territory.

    The attack was a success, but the relationship between Ieyasu and Shingen fell apart almost immediately. According to Tokugawa accounts, it had been agreed that Ieyasu would take Totomi Province, and Shingen would take Suruga. However, it wasn’t long before Takeda forces were also crossing into Totomi, in direct violation of the agreement (which may never have existed to begin with).

    Suruga and Totomi Provinces.
    By Ash_Crow – Own work, based on Image:Provinces of Japan.svg, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=1691864

    Ieyasu then sought the support of the Hojo Clan, and their Lord, Ujiyasu, who had his own ambitions for the former Imagawa territory. Together, they successfully pushed the Takeda forces back, and in 1570, Ieyasu moved his base from Okazaki Castle in Mikawa Province to Hikuma, which he promptly renamed Hamamatsu, in Totomi. Later that year, he would further prove his value as an ally of Oda Nobunaga by supporting his campaign against the Azai-Asakura Alliance, fighting in the rearguard in the defeat at Kanegasaki, and then providing important reinforcements at the victorious Battle of Anegawa in July.

    In 1571, the alliance would be sorely tested, as the last Ashikaga Shogun, Yoshiaki, sought to rally forces in opposition to Oda Nobunaga, with the ultimate goal of restoring his family’s position. The Anti-Nobunaga coalition (which was, importantly, not necessarily pro-Ashikaga) included the forces of the Azai-Asakura Alliance, the powerful temple of Ishiyama Honganji, and Takeda Shingen, among others.

    Ashikaga Yoshiaki

    In the aftermath of the defeat of the Imagawa, Hojo Ujiyasu, who had favoured an alliance with Ieyasu against the Takeda, died and was replaced by his son, Ujimasa, who reversed his clan’s diplomatic position and reestablished the alliance with Shingen. At this point, Yoshikai, seeking to take advantage of the pressure he was now under, sought to gain Ieyasu’s support, offering him the position of Kanrei or deputy Shogun in exchange.

    Ieyasu refused this offer and chose to retain his alliance with Nobunaga; in response, Takeda Shingen launched an invasion of the Mikawa and Totomi Provinces in September 1572. Leading 20,000 troops, Shingen crossed the Aokuzure Pass, and with the help of several defections amongst Ieyasu’s retainers, swiftly gained control of northern Totomi.

    A later depiction of the Takeda Army advancing into Totomi Province.

    Meanwhile, a separate force invaded Nobunaga’s territory in Mino, meaning that when Ieyasu called for aid, none was readily available. Ieyasu was forced into an impossible situation; his forces were heavily outnumbered by the advancing Takeda, and a pitched battle would almost certainly end in defeat. On the other hand, if he retreated or even stayed on the defensive, he faced the prospect of losing support from his retainers, some of whom had already proved they were willing to switch sides.

    The Takeda headed towards the strategically important Futamata Castle, and Ieyasu had no choice but to try to head them off. The advance guards of both armies clashed at the Battle of Hitokotozaka, and the Tokugawa were soundly beaten, causing them to retreat to the relative safety of Hamamatsu, and giving the Takeda a clear path to lay siege to Futamata, which fell shortly afterwards.

    The remains of Futamata Castle.
    CC 表示-継承 3.0, https://commons.wikimedia.org/w/index.php?curid=427661

    In the aftermath of this disaster, still more Tokugawa retainers switched sides and joined the Takeda, and it was assumed that Shingen, whose army, strengthened by defections and reinforcements, now stood at around 30,000 men, would march on Hamamatsu. Instead, the Takeda forces bypassed it entirely. It has been suggested that this was a ploy to lure Ieyasu out of the powerful fortress, giving Shingen the opportunity to destroy him in the open.

    If that was the plan, it worked, and despite urging from his retainers to remain in Hamamatsu, Ieyasu was emboldened by some long-awaited reinforcements from Nobunaga and decided to march out and intercept the Takeda. The result was the disastrous Battle of Mikatagahara, in which the Tokugawa were decisively defeated, with Ieyasu himself only being saved by the bravery of his retainers, who fought a rearguard action so ferocious that Ieyasu was allowed to escape, and the Takeda were convinced to call off the pursuit.

    A later depiction of the Battle of Mikatagahara

    The winter of 1572 saw the Takeda forces camping deep inside Tokugawa territory, whilst Ieyasu himself was holed up in Hamamatsu, his army scattered, and his prospects looking very bleak.

    A painting of Ieyasu supposedly made after the defeat at Mikatagahara. Traditional history suggests that Ieyasu commissioned the painting as a reminder of the defeat and a warning against future arrogance; however, this account doesn’t appear in any sources before the 20th century and is now generally believed to be apocryphal.

    Sources
    https://ja.wikipedia.org/wiki/%E5%BE%B3%E5%B7%9D%E5%AE%B6%E5%BA%B7
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  • The Third Unifier – Tokugawa Ieyasu. Part One.

    The Third Unifier – Tokugawa Ieyasu. Part One.

    If the bird will not sing, wait for it to sing.

    The third, and ultimately, final unifier was born Matsudaira Takechiyo in December 1542. His father, Matsudaira Hirotada, is a somewhat mysterious figure, with several theories about the events of his life, and even his death, but what is known with (relative) certainty is that the Matsudaira Clan were the lords of Okazaki Castle in Mikawa Province, which is where Takechiyo (from now on, referred to as Ieyasu) was born.

    At the time of his birth, the Matsudaira Clan were a relatively minor family in the service of the more powerful Imagawa. This was an era of constant civil war, and plots, subterfuge, and outright betrayal were common. To pre-empt this, in 1547, when Ieyasu was about five, he was sent to the Imagawa capital at Sunpu (in modern Shizuoka) as a hostage to secure his father’s loyalty.

    A modern reconstruction of Sunpu Castle.
    江戸村のとくぞう – 投稿者自身による著作物, CC 表示-継承 4.0, https://commons.wikimedia.org/w/index.php?curid=95206213による

    The boy’s escort was entrusted to one Toda Yasumitsu, who promptly betrayed the Imagawa and instead had Ieyasu sent to Oda Nobuhide. Quite why Yastumitsu did this is debated, with some sources saying he sold Ieyasu for 1000 gold pieces (some say 100), and that the Imagawa promptly attacked his castle, and destroyed his family (though other sources say the Toda held out for a year or more).

    Other sources say that the whole thing was actually a ruse arranged by Ieyasu’s father, who had secretly agreed to swear fealty to the Oda and had sent his son as a hostage as proof. It is also suggested that this was the first time Ieyasu met Oda Nobunaga, though historians debate whether the meeting actually took place.

    Oda Nobunaga, who may (or may not) have met Ieyasu during his time as a hostage.

    Despite the somewhat murky circumstances, Ieyasu’s time as a hostage would not last long, as his father soon passed away (the exact date and circumstances are debated), aged around 23-24, and the Lord of the Imagawa, Yoshimoto, arranged a hostage swap that saw Ieyasu brought to Sunpu, where, despite now being the nominal lord of Okazaki, the Imagawa meant to keep a close eye on him.

    This is another page in Ieyasu’s history that the sources disagree on. Some suggest he was still a hostage, whilst others point out that, as the Lord of Okazaki, he was a direct vassal of the Imagawa, and instead, his residence in Sunpu was part of a wider policy of keeping vassals in a central location. Either way, Ieyasu was hardly kept in the dungeons, and in 1557, he married Yoshimoto’s niece, Lady Tsukiyama. (Tsukiyama is a place near Sunpu; her real name is not recorded.)

    Lady Tsukiyama, Ieyasu’s first wife. Her real name may have been Sena, but that name doesn’t appear in the records until 1740, 160 years after her death.

    A marriage to a close relative of Yoshimoto boosted Ieyasu’s standing within the clan, but it may also have played a part in the Imagawa’s own ambitions. For decades, the Kira Clan, descendants of the Ashikaga Shoguns, had held a preeminient position in Mikawa Province. Though not officially governors (shugo) of the Province, their illustrious descent meant that, at least in terms of lineage, they were equals to the Imagawa.

    As we have seen dozens of times before, however, during the Sengoku Jidai, the prestige of an illustrious name wasn’t what it had once been, and the real power in Mikawa lay with the Matsudaira. By binding Ieyasu more closely to his family, Imagawa Yoshimoto sought to use this power to assert Imagawa control over the Province at the expense of the Kira and the other Mikawa Clans.

    Mikawa Province.
    By Ash_Crow – Own work, based on Image:Provinces of Japan.svg, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=1683118

    These ‘other clans’ weren’t all that happy to see the Imagawa take over, however. Much like the rest of the realm, the minor lords of Mikawa were an independent-minded bunch and were more content to rule themselves. An initial outbreak of rebellion was crushed in 1557, only to begin again a year later. This time, Yoshimoto dispatched Ieyasu to play a part in putting the rebellion down, and he got his first taste of battle at the Siege of Terabe Castle in March 1558.

    Ieyasu earned praise from Yoshimoto and some of his vassals for his diligent approach to warfare. Later records suggest that he recognised that simply taking Terabe Castle wouldn’t be enough to fully subdue the rebels, so he set about burning the castle town and then several other settlements nearby. This may not sound like praiseworthy behaviour to you and me, but Yoshimoto was so impressed he rewarded Ieyasu with land and a shortsword.

    Imagawa Yoshimoto

    With the rebellion in Mikawa crushed (for now), Ieyasu turned to securing his position as future lord of Okazaki and eventual master of the whole Province. The problem was that Ieyasu was still largely a stranger to the Mikawa Clans. He had been absent from the Province for most of his young life, first a hostage of the Oda, and later residing in the Imagawa Capital at Sunpu.

    To resolve this, Ieyasu issued a seven-point decree outlining his relationship with his vassals. This decree was significant because it made it clear that, should Ieyasu’s vassals feel that he is ruling badly or ignoring their advice, they could appeal to Ieyasu’s father-in-law, Sekiguchi Ujizumi, who remained a powerful figure within the Imagawa Clan hierarchy, suggesting that, at least as late as 1559, Ieyasu intended to remain loyal to the Imagawa.

    A later depiction of a battle in Mikawa Province. Like many minor clans at the time, the warriors of Mikawa were a fiercely independent bunch who would fight viciously to preserve that independence.

    Since the time of Ieyasu’s Grandfather, the Matsudaira of Mikawa Province had been involved in a long-term conflict with the Oda Clan of neighbouring Owari. When the Mikawa and the Matsudaira came under the Imagawa banner, their new overlords inherited the conflict.

    During the rebellion in 1556 and 1558, Oda had supported the anti-Imagawa forces, and Yoshimoto, weary of their interference, made the decision to crush them once and for all, which would have the added bonus of clearing his path to Kyoto. In preparation, Ieyasu was ordered to lead the vanguard and attack several border forts.

    The site of Otaka Castle as it appeared in February 2014.
    Tomio344456 – 投稿者自身による著作物, CC 表示-継承 4.0, https://commons.wikimedia.org/w/index.php?curid=86415730による

    He captured two forts and then lifted the siege of Otaka Castle, making it his temporary base. However, news arrived that Yoshimoto had been defeated and killed in a surprise attack at Okehazama. At that, Ieyasu retreated back to Okazaki to plan his next move. Historians debate whether Ieyasu intended to betray the Imagawa right away, or if the decision was a reaction to events, but in early 1561, he attacked Ushikubo Castle, an Imagawa stronghold in Mikawa, signalling his change of allegiance.

    It is generally accepted that Ieyasu’s change of heart was brought about by the decision of the Imagawa’s new Lord, Ujizane, to prioritise fighting against the Takeda and Hojo, over the Oda, leaving Ieyasu to fend for himself against Oda Nobunaga, who was very much in the ascendancy after his surprising victory at Okehazama.

    A 19th-Century depiction of the Battle of Okehazama, showing Imagawa Yoshimoto (the figure on the left) facing his demise.

    The long standing animosity between Mikawa and Owari meant that neither side found it easy to stomach making peace, however, with Nobunaga facing serious issues against the Saito Clan to the north, and Ieyasu having to deal with the vengeful Imagawa, both sides swallowed their pride, and, in 1562, agreed to the so-called Kiyosu Alliance, bringing into existance one of Japanese history’s most important partnerships.

    Sources
    https://ja.wikipedia.org/wiki/%E5%BE%B3%E5%B7%9D%E5%AE%B6%E5%BA%B7
    https://ja.wikipedia.org/wiki/%E6%B8%85%E6%B4%B2%E5%90%8C%E7%9B%9F
    https://ja.wikipedia.org/wiki/%E7%89%9B%E4%B9%85%E4%BF%9D%E5%9F%8E
    https://ja.wikipedia.org/wiki/%E5%90%89%E8%89%AF%E6%B0%8F
    https://ja.wikipedia.org/wiki/%E4%B8%89%E6%B2%B3%E5%BF%A9%E5%8A%87
    https://ja.wikipedia.org/wiki/%E7%9C%9F%E5%BC%93%E5%B1%B1%E5%9F%8E
    https://ja.wikipedia.org/wiki/%E5%90%89%E8%89%AF%E7%BE%A9%E5%AE%89
    https://ja.wikipedia.org/wiki/%E5%AF%BA%E9%83%A8%E5%9F%8E%E3%81%AE%E6%88%A6%E3%81%84
    https://ja.wikipedia.org/wiki/%E5%BE%B3%E5%B7%9D%E5%AE%9F%E7%B4%80
    https://ja.wikipedia.org/wiki/%E7%AF%89%E5%B1%B1%E6%AE%BF
    https://ja.wikipedia.org/wiki/%E9%96%A2%E5%8F%A3%E6%B0%8F%E7%B4%94
    https://ja.wikipedia.org/wiki/%E6%88%B8%E7%94%B0%E5%BA%B7%E5%85%89
    https://ja.wikipedia.org/wiki/%E7%94%B0%E5%8E%9F%E5%9F%8E_(%E4%B8%89%E6%B2%B3%E5%9B%BD)
    https://ja.wikipedia.org/wiki/%E9%A7%BF%E5%BA%9C
    https://ja.wikipedia.org/wiki/%E6%96%BC%E5%A4%A7%E3%81%AE%E6%96%B9
    https://ja.wikipedia.org/wiki/%E6%9D%BE%E5%B9%B3%E5%BA%83%E5%BF%A0