Ruth Willemse grew up in a musical family that loved to sing. In her childhood, she experienced "God" through music and singing together in the church, which she has since exchanged for the opera stage. Here, being part of the music can still be a metaphysical experience.
Ruth began classical singing in 2005 at the Conservatorium van Amsterdam (Conservatory of Amsterdam) while completing her Master's degree in Musicology at the University of Amsterdam. She wrote a thesis and did practical research on the transmission of emotion in classical vocal music. In 2013 she received her Master's degree in Vocals at the Prince Claus Conservatoire.
Ruth regularly performed in song recitals; she is part of a duo with pianist Vital Stahievitch with whom she recorded songs by Mahler, Elgar and Wagner in 2018, released by ETCETERA-Records. She performed in operas and song recitals at festivals such as the Grachtenfestival and the Peter de Grote Festival. On the concert stage, Ruth has performed mezzo or alto parts, such as the St. Matthew Passion, the Messiah, Mozart's Requiem, Haydn's Harmoniemesse, Saïnt-Saëns' Oratorio de Noël, Elgar's Sea Pictures and Mahler's Rückert-Lieder.
In 2015, she made her debut with Dutch National Opera as Maddalena in Reimsreisje (a children's performance based on Il Viaggio a Reims). In 2016 she made her debut in the NTR Matinee as Madre di Cio-Cio-San in Puccini's Madama Butterfly. With the Nederlandse Reisopera, Ruth sang various roles such as Kate Pinkerton in Madama Butterfly, Berta in Rossini's Il Barbiere di Siviglia and Old Lady in a pocket version of Bernstein's Candide. She performs various opera roles with other companies or at festivals, the most recent of which is Petrovna (neighbour) in Stravinsky's Mavra with the Nederlands Blazersensemble in 2022.