Takatomo was a younger son of Yûki Masatomo and became heir to the Ôyama family of Shimotsuke province. He clashed with the Nasu family and later submitted to the advances of Uesugi Kenshin and became an ally of the latter. Takatomo's second son Harutomo was adopted by the former's brother Masakatsu.
References
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005