She was born in Czeliewy, Poland, and studied art in Warsaw and Krakow and at the Academie Julian in Paris in mid-1890’s. At a wedding on the island of Jersey, where she was a bridesmaid, she met the painter Robert Bevan and married him shortly after that. After their marriage in 1898 they settled in England. They were both founder members of the London Group with whom they exhibited for many years.
In March of 1910, Huntly Carter said of her work, “what S. de Karlowska has to say she tells us lucidly in pure and harmonious colour. Her two studies of still life speak in the broadest, simplest, and most convincing terms” NA 6.19:452.
De Karlowska held her first solo show in 1935 at Adams Gallery, which gave a memorial exhibition in 1952. The Tate Gallery holds examples of her work.