The Battle of Sekigahara

 The Battle of Sekigahara

 

Today (by one measurement) is the anniversary of the Battle of Sekigahara, it’s taking place in 1600 and being a if not the foundational event in the history of Japan. FYI, an alternative dating is October 21.

 

Sixteenth century Japan, while nominally led by the Emperor, was controlled by regional lords; the Emperor was a figurehead without effective control. The Sixteenth century had seen an ebb and flow of various clans including that of the famous Takeda Shingen. There then arose first Oda Nobunaga, he overthrowing the nominal but ineffective Ashikaga Shogunate and significantly consolidated power in central Japan under his Oda clan.  He was, however, famously forced to commit seppuku (although it is possible he died fighting) during the Honnō-ji Incident (1582) when his retainer Akechi Mitsuhiderevolted and attacked Nobunaga’s weakly defended position.  Mitsuhide was subsequently killer at the Battle of Yamazaki, it taking place some two weeks after Nobunaga”s death.

 

Nobunaga was nominally succeeded by a grandson, Oda Hidenobu, but as he was just a child the fact of his succession was consequent to the support of Toyotomi Hideyoshi, one of his father’s retainers. Having nothing to do with this discussion, Hidenobu would later convert to Catholicism. But I digress.  Toyotomi Hideyoshi would continue Nobunaga’s program of unification, and although a peasant (he was not born a member of the samurai class) he was by means of an astute adult adoption into the Fujiwara Clan appointed to the highest offices in the land including Imperial Regent; however, he could not reinstate the shogunate in himself as not being born a samurai he could not be the chief samurai. In 1592, after the death of his only son, he adopted and appointed as his heir his nephew Hidetsugu. Thereafter, resigning from his Imperial offices, he was known as the Taiko (retired regent). But then in 1593 Hideyoshi has another son, Hideyori, and tension as to the succession grew. Hideyori was 5 years old when Hideyoshi died in 1598.

 

Tokugawa Ieyasu had like Hideyoshi been a retainer and general under Nobunaga, including having fought at the Battle of Yamazaki. After Nobunaga’s death and a bit of back and forth he entered Hideyoshi’s service but on less than a full vassal basis.  When Hideyoshi died Ieyasu was one of the five members of a regency council (Tokugawa Ieyasu, Maeda Toshiie {succeeded in 1599 by his son Maeda Toshinaga}, Ukita Hideie, Uesugi Kagekatsu, and Mori Terumoto) intended to rule Japan until Hideyori came of ago, which was 15. However, relations among the regents broke down and Ieyasu, by far the most powerful of the five, used the pretext of improper actions by Uesugi Kagekatsu to launch a war that culminated in the Battle of Sekigahara. 

 

Ishida Mitsunari led the forces at least nominally loyal to Hideyori, they (the Western Army) comprising by the time of battle some 80,000 soldiers (their force had been larger but there had been on the eve of battle significant defections to Ieyasu’s side).  Ieyasu went into battle with approximately 88,000 troops (the Eastern Army).  In a day that started with heavy fog the forces clashed. As the day progressed there were several notable defections from the Western Army to the Eastern army (maybe 23,000 troops total), in each case weakening the former and strengthening the latter.  In the end the battle lasted between 2 and 4 hoursduring which the Eastern Army suffered between 8,000 and 35,000 deaths while the Eastern Army is estimated to have lost between 4,000 and 10,000. Taking the middle point of the higher of these ranges the Eastern Army, initially not that much different in size from the Eastern Army, suffered 17,500 casualties while Ieyasu’s Eastern Army suffered 5,000.  Ieyasu then began a program of redistribution of territories to favor those who had supported his position as those who were part of the Western Army and who did not defect were stripped of their lands and power. Hideyori was forced to commit seppuku when Ieyasu’s forces laid siege to his remaining forces in Osaka Castle.

 

In 1603 Tokugawa Ieyasu was appointed Shogun by the Emperor, thus starting the Tokugawa Shogunate that would rule Japan until 1868.

 

And thus was Japan unified by the sequential acts of Oda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu.

 

For those of you who enjoyed the 2024Shogun tv series (the recent one, not whatever that was circa 1980 with Richard Chamberlain), it is set in this period, but significant aspects of it, well, lets just say they depart from the historic record in order to tell a story.  There was an English sailor, a navigator, named William Adams who was a retainer to Tokugawa Ieyasu.  The chronology of his arrival and place in the Tokugawa court do not match that in the tv series or Clavell’s book.