[1] Szaniawski was born into a family of Polish landed gentry at an estate in Zegrzynek in east-central Poland under foreign partitions.

[1] In the 1920s Szaniawski wrote a whole series of stage plays, notably: Papierowy kochanek (Paper-made Lover, 1920), Ewa (1921), Lekkoduch (Trifler, 1923) performed by Reduta; as well as Ptak (Bird, 1923), Żeglarz (Sailor, 1925), and Adwokat i róże (Attorney and roses, 1929) which won the national literary prize a year later.

[1] At 76, Szaniawski married a fine-art painter Anita Szatkowska, who was some twenty years younger and suffering from a mental disorder.

[2] According to witness accounts, Szaniawska (née Szatkowska) starved and abused her husband physically, fed him dissolved plaster as "medicine", and isolated him entirely from the world, until his death in 1970.

[2][3] It is widely assumed that it was she who set his country estate on fire in Zegrzynek in 1977, causing the death of two squatters locked inside.