Ida Simons was born Ida Rosenheimer to a well-to-do Jewish merchant family in Antwerp, Belgium. Her parents Moritz (Maurits) Rosenheimer and his wife Constance Vecht brought her up to speak Flemish, German, English, Dutch and Yiddish. She went to The Netherlands with her parents as a small child during World War I. After completing her musical studies in London and Paris, she made her debut as a concert pianist at age 19. She received great acclaim and performed with many leading European orchestras. In 1933, she married David Simons, a lawyer, with whom she had a son. As a pianist, Ida continued to perform under the name Rosenheimer. Her career was brought to an abrupt halt by the Nazi Occupation of World War II. With her family, she was interned at Kasteel de Schaffelaar and Westerbork, and deported to the concentration camp at Theresienstadt. She survived the war, but her health was broken, forcing her to abandon her ambitions as a pianist in 1953. By this time, she had begun writing. She made her debut as a poet in 1946 with the collection Wrange oogst (Bitter Harvest). It was followed by a volume of novellas entitled Slijk en sterren (Muck and Stars), published in 1956 under the pseudonym C.S. van Berchem. Her best-known work is probably the semi-autobiographical novel Een dwaze maagd (A Foolish Virgin), which first appeared in 1959. After her untimely death at age 49, her work sank into oblivion, but since its revival in 2014, it has been translated into more than 15 languages and published widely.