The Ôsaki of Mutsu province were locally powerful from the middle of the 14th Century. They suffered a long period of internal strife starting in 1536 and were forced to call on Date Tanemune for assistance. Afterwards the Ôsaki came under Date influence.
References
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005