Saitō Dōsan

Timeline

1. 1533–1538Mino Province · Mino ProvinceDocuments first mention 'Fujiwara Kishū' and 'Nagai Kishū' in 1533, showing he had inherited his father's position in the Nagai faction in Mino. After Saitō Toshiyoshi died around 1538, he adopted the Saitō surname, calling himself Saitō Yamashiro-no-kami Toshimasa, gradually gaining control of shugo-dai level military and political resources.
2. 1541–1542Inabayama Castle · Mino ProvinceFalling out with shugo Toki Yoriaki around 1541, he attacked his Ōsaki Castle and forced him into flight, becoming the de facto ruler of Mino around 1542. Using Inabayama Castle as his base he carried out extensive renovations, eliminating rivals through assassination, marriage alliances, and force, being called the 'Mino Viper' by contemporaries and becoming a typical example of Sengoku gekokujō.
3. 1547–1548Inabayama Castle · Mino ProvinceIn 1547 Oda Nobuhide launched a major attack on Inabayama; Dōsan shut himself in the castle and counterattacked, heavily defeating the Oda forces at Kanagaguchi. The following year the two sides made peace, and Dōsan married his daughter Kichō (Nōhime) to Nobuhide's heir Oda Nobunaga. According to the Shinchō Kōki, after meeting at Shōtoku-ji he completely changed his view of Nobunaga as a 'great fool,' predicting that his own son would hold the reins for Nobunaga.
4. 1554–1556Banks of the Nagara River · Mino ProvinceIn 1554 he ceded the family headship to his eldest son Yoshitatsu, tonsured at Jōzai-ji and taking the name Dōsan, retiring to Sakisawa Castle. Favoring his youngest son and suspecting Yoshitatsu was not his own child, father and son fell out. In 1556 Yoshitatsu rose in revolt; the two sides fought a decisive battle at the Nagara River, where Dōsan, outnumbered, was killed. Nobunaga came to his aid but arrived too late; on his deathbed Dōsan is said to have ceded Mino to his son-in-law.