After expelling Yoshiaki, Nobunaga moved to Azuchi near Kyoto and built the grand Azuchi Castle and continues to subdue feudal lords of various regions. However, he loses his life in 1582, from an attack by his vassal, Akechi Mitsuhide, at Honno-ji Temple in Kyoto.
Toyotomi Hideyoshi, a vassal of Nobunaga, was the one to succeed him and unify Japan. After defeating his master’s foe, Mitsuhide, he starts to establish himself as the successor of Nobunaga. He then constructs Osaka Castle, but Nobunaga’s second son, Nobuo, rebels against him. Nobuo banded together with Tokugawa Ieyasu, Nobunaga’s ally, and a battle is fought at the border of Nobi (Battle of Komaki and Nagakute). The battle lasted for more than half-a-year, and although the Ieyasu-Nobuo army was winning, the battle was ended due to Hideyoshi and Nobuo making peace, and Ieyasu retreating. Thereafter, Hideyoshi manages to unify all of Japan in only 8 years and establishes a stable system of governance.
However, after Hideyoshi’s death, in opposition to Tokugawa Ieyasu who breaks Hideyoshi’s rules and strengthens his own forces, those who aim to follow the rules such as Ishida Mitsunari take up arms. Hearing news of this, Ieyasu also raises an army with anti-Ishida feudal lords and the two forces battle at Sekigahara, Gifu Prefecture (Battle of Sekigahara). Although it was a decisive battle with approximately 84 thousand soldiers on Mitsunari’s side (West Army) and 74 thousand soldiers on Ieyasu’s side (East Army), there were many military commanders who betrayed the Mitsunari army or didn’t join the fighting, and the battle which lasted for several hours was easily won by Ieyasu’s army.