Sawamura, whose original name was Yūichi Katō, was born in Tokyo to the kabuki actor Denzō Takeshiba.

[1] He began his movie career at the film studio Makino Productions in 1929, and later moved to Nikkatsu, working most of the time in jidaigeki.

Both Sawamura's own family and that of his wife were active in the film industry.

Masahiro married the actress Yukiko Todoroki and their son—and thus Sawamura's nephew—Masayuki Makino, is the head of the Okinawa Actor's School.

Sawamura fathered the actors Masahiko Tsugawa and Hiroyuki Nagato, both of whom married famous actresses, Yukiji Asaoka and Yōko Minamida respectively.