Jacoba Johanna (Coba) Ritsema was born in 1876 into a family where the talk was often about art. Her father was a printer and book dealer. So nothing was laid in her way when she expressed a desire to study painting. At 15 years old she entered the Haarlem School for Applied Arts, from where she gained admission to the State Academy of Fine Arts in Amsterdam. Coba was not the only woman to study at the academy - she and the other female students took their lessons apart in a "ladies' painting class", from which they derived an early sense of solidarity and a common destiny. Together with other "lady artists", Ritsema frequented artists associations, with meetings often taking place in the homes of the members. New bohemians Ritsema and girlfriends such as Marie van Regteren Altena, Lizzy Ansingh and Jacoba Surie - all from good homes and with no money worries - were baptised in 1912 "the Amsterdam Joffers".
The Joffers exhibited together and socialised together - drinking tea, celebrating birthdays, for over twenty years in and around Amsterdam. While not exactly driving a feminist wave, they did contribute to a growing acceptance and appreciation for women in art. Ritsema's preference was for still lifes and portraits, and it is the still lifes that show her at her best. In 1957 she received the 5-yearly Rembrandt Prize. She had kept, observed the jury, the fire of the true art of painting alight" and distinguished herself by the "fine use of tone and colour, her broad vision and her gift for composition". Coba Ritsema's work is found in nearly all the large Dutch museums and many international private collections. She died in 1961.