Born into a migrant family of Austrian and Swedish descent, Curl grew up in poverty and began work as a fruit-picker at the age of eight.

[1] During her high school career Curl worked part-time as a housekeeper for a local family, who encouraged her to expand her knowledge through literature.

Martina started to keep a dictionary which she used to look up unfamiliar words, and avidly read Charles Dickens and Greek dramas.

By 1936 she joined the communist party, and applied for a position with the Federal Arts Project which started her professional artistic career.

[2] She advocated for workers rights, and believed socialism bridged the gap between the Christian ideals she had been taught as a child and the reality of capitalism.

While she gained fame in the late 1930s due to her association with other artists and activists, she believed her radicalism prevented her from attaining more mainstream success.