She was the illegitimate child of the Polish impressionist painter Aniela Pająkówna and the writer Stanisław Przybyszewski, the latter a famous and notoriously dissolute modernist who was one of the founding members of the Young Poland movement.

Initially her parents' friends Wacław and Zofia Moraczewski paid for her education, but from 1914 it was her aunt (her mother's sister) Helena Barlińska who took care of the girl.

Between ages ten and fifteen Przybyszewska attended four different schools in three countries: France (Paris), Switzerland (Zürich, 1912-1914), and Austria (Vienna and Oberhollabrunn).

Although she was an outstanding student, Stanisława was sharply critical of both how and what she was taught, and she considered herself essentially self-educated, since her own special interests led her to the exact sciences, above all mathematics and astronomy.

In 1920, not without Przybyszewski’s involvement, Stanisława moved to Poznań where she established connections with the expressionistic circle of the journal, The Source, and studied music at the conservatory.

[2] In 1922 she moved to Warsaw and found a job as a salesgirl in a Communist bookstore; this employment, in the recent aftermath of the Polish-Soviet War, led to her being arrested for a week in Poznań (her official place of residence) before being released for lack of evidence.

Stanisława made not a single lasting friendship during her year in Warsaw, but as a result of her incarceration she grew obsessed with the victims of unjust imprisonment and judicial oppression, starting with Robespierre and going up to Sacco and Vanzetti in her own time.

From Polish writers she valued Joseph Conrad[4] and Juliusz Kaden-Bandrowski, and considered Stefan Żeromski as having huge talent which didn't develop.

[5] She did not have any stable financial income: the state scholarship that she received in unequal amounts from 1929 to 1933 was not enough to survive, so Przybyszewska depended heavily on the support from Barlińska and Bennet.

"[7] One of Mantel's 2017 Reith Lectures on BBC Radio Four, Silence Grips the Town, delivered in Antwerp, was dedicated to Przybyszewska.