So Yamamura was a Japanese actor and film director. He appeared in more than 110 films between 1947 and 1991, and directed four films. He was also known by the name Satoshi Yamamura, while his actual birth name is Koga Hirosada. In the US, he is well known for his portrayals of Japanese Admiral Isoroku Yamamoto of the Combined Fleet, in Tora! Tora! Tora!, and of Mr. Sakamoto, the CEO of Assan Motors in Gung Ho.