Who Is Saito Yoshitatsu (Saitō Yoshitatsu)?
Heir of Mino who killed his father, Dosan
Saito Yoshitatsu was a Warring States warlord of Mino Province and the son of Saito Dosan. Although his father handed the province to him, the two later fell out, and he raised an army and killed Dosan at the Battle of Nagara River in 1556. He appears in the Shinchō Kōki under the name "Shinkuro."
According to the Shinchō Kōki, Dosan thought Yoshitatsu a fool and doted on his younger brothers. So Yoshitatsu pretends to be ill, summons two of his brothers, and has them killed. He then fights his father with a large army and defeats him at the Nagara River. Nobunaga sets out to help Dosan but arrives too late and loses his father-in-law. The episode mirrors the later scene in which Nobunaga feigns illness to summon his own brother.
One story claims Yoshitatsu was not Dosan's real son but the child of Toki Yorinori, the former ruler of Mino, but nothing is certain. He died of illness in 1561, and under his son, Tatsuoki, Mino was conquered by Nobunaga.
