Her rivalry with another popular geisha singer, Katsutaro Kouta, created the "Katsu-Ichi Era" in Japanese music history.

She spent much of her early years working at a hot springs spa in Asama, located in the Nagano Prefecture as an ordinary geisha.

Due to her great singing talent, Ichimaru was asked by The Victor Recording Company to sign a contract in 1931, along with another popular geisha singer, Katsutaro.

In 1950, she became the first Japanese singer after World War II to be invited to Hawaii to perform, along with Noboru Kirishima, Akiko Futaba and Masao Koga.

She was also granted the title of Head Master of Nakamura School of Edo Ko-uta in 1960, due to her successful singing career and her support of the style.

Throughout her career she recorded two-hundred-seventy pieces of ha-uta, zokkyoku melodies and ko-uta, and won many prestigious awards including Geijutsusai Shorei Sho in 1970, Shiju Hoso (Imperial Order of the Purple Ribbon) in 1972 and Kun Yonto Zui-ho Sho (4th Imperial Order of the Sacred Treasure) in 1981.

The May–June 2003 issue of the magazine Arts of Asia contained a twenty-page article about Ichimaru, which included an eight-page spread dedicated to some of her kimono.