Saito Dosan (born 1494) was known as the Viper of Mino due to his ruthlessness both on the battlefield and in administrating his domain. Dosan was originally not a samurai, but a wealthy oil merchant hailing from around Kyoto, before gaining a position under Nagai Nagahiro of Mino (Gifu), and later becoming a retainer of Toki Yorinari, Governor of Mino. Dosan ousted the Toki, and assumed power of Mino, basing himself in Inabayama Castle.
(Inabayama would later be taken by Oda Nobunaga and re-named Gifu.) At the time the Toki clan were allied with the neighboring lords of Owari (western Aichi Prefecture) the Oda clan. In 1547, the Oda clan were defeated in the Battle of Kanoguchi. Victory for the Saito also brought recognition across the nation. The two clans reached a truce through a deal where Saito Dosan’s daughter, Kicho, (better known as Nohime) would marry Oda Nobuhide’s son, Nobunaga. Known for his ruthless tactics, he received a taste of his own medicine when he was ousted by his own son Yoshitatsu in a coup d’etat 1556. Yoshitatsu had been named as heir to the Saito clan, and was based in nearby Sagiyama Castle, given to him by his father in 1548. Yoshitatsu, fearing disinheritment, attacked and killed his two brothers, which led to father and son fighting each other in the Battle of Nagaragawa. The 62 year old Dosan’s head was taken by a samurai named Komaki Genta and is now interred in the Jozai-ji, a temple in Gifu, not far from Gifu Castle.