In order to understand the Battle of Sekigahara, I should tell you about Hideyoshi Toyotomi
Hideyoshi was born to a farming family in Owari country, Aichi-gun, Nakamura (Nakamura-ku, Nagoya city) in 1537. He was
born under the name of Tokichiro Kinoshita. However after being promoted in 1566, his name changed to Hideyoshi Hashiba and then finally around 1586 to Hideyosi Toyotomi.
Although, he served under Shogun Nobunaga Oda as a common foot soldier in 1554, he showed that he was a brilliant
strategist and that he had superior leadership which enabled him to take up an important job in the army.
Daimyo Asai lost the fight with Oda’s forces, and his forces were destroyed, Nobunaga gave Hideyoshi north Oomi in the
former territory of Asai. Hideyoshi gathered many excellent young men, such as Mitsunari Ishida, in this territory.
Nobunaga ordered Hideyoshi to march towards the Chugoku Region in 1576. In those days, the Chugoku Region was under the
control of General Mori. When Hideyoshi was attacking Takamatsu Castle in 1582, he heard the news that Nobunaga killed himself in the rebellion caused by his subordinate Mitsuhide Akechi in
Honnoji temple (Honnoji-Temple Incident)
Hideyoshi realized his chance to take power and made peace with General Mori in order to take revenge for Nobunaga,
then returned to the Kyo with a larger army than he went. (a quick return from the Chugoku
Mitsuhide was astonished by the march of Hideyoshi and his lightning speed. He fought against Hideyoshi in Yamasaki, Kyo. Relizing he was over matched, Mituhide retreated
only to be killed by warrior hunting (battle of Yamasaki).