[1] Yamamura was born Koga Hirosada in Tenri, Nara Prefecture, and graduated from the University of Tokyo.

[2] In 1942, Yamamura and Isao Yamagata formed the Bunkaza Theatre Company.

[2] In the US, he is well known for his portrayals of Japanese Admiral Isoroku Yamamoto of the Combined Fleet in Tora!

He played the role of Tokugawa Ieyasu in the taiga drama Haru no Sakamichi in 1971.

[6] His major historical roles were Yagyū Munenori in the 1978 The Yagyu Conspiracy and Hoshina Masayuki in the 1980 Shadow Warriors.