Baku Ishii is widely regarded as the creator of Japanese modern dance. He was born in Mitane-cho, Akita Prefecture in 1886. Despite his difficulty adapting to school life in his early years, he moved to Tokyo at the age of twenty-four to study literature. Eventually, he began studying the violin at the Imperial Theatre. During the course of his violin studies, however, Ishii, moved by his exposure to opera, decided to focus on dance. While he remained at the Imperial Theatre, his new focus led him to study ballet under Giovanni Rossi, a ballet instructor who previously worked in the UK, but who had been invited to teach at the Imperial Theatre by the then managing director Keinosuke Nishino. Ishii also performed in the operas Rossi produced at the Imperial Theatre.

Ishii eventually resigned from the opera as a result of an argument with Rossi. After leaving Rossi, Ishii studied rythmique (eurhythmics) with Émile Jaques-Dalcroze. Later he began to choreograph his own work.