Born deaf and dumb, Slava Raškaj expressed herself through painting from her earliest years. At the age of eight, she went to Vienna where she attended the Taubstummeninstitut. There, she started to draw with pencils and etch, and she also learnt the art of the vignette, a decorative drawing much sought after in magazines and books at the beginning of the Vienna pre-Secession. Back in Ozalj, she continued to draw, in particular floral motifs, and discovered watercolours, a technique at which she would excel. In 1895, Raškaj settled in Zagreb, where the director of the Deaf and Dumb Institute offered her a studio in the premises of a former morgue. The painter Bela Csikos Sesia taught her drawing and academic painting. Under his authoritarian influence, she painted still lifes in gloomy colours, with rare light details, whereas in Ozalj her landscapes were awash in light.

In 1898, she left Csikos Sesia, travelled with her mother, and returned to live in the family home in Ozalj, where she painted outdoors. From then on her painting took a more personal turn. In 1910, the first signs of psychic disorder appeared. Committed to the psychiatric asylum of Stenjevac, near Zagreb, Raškaj died there four years later. No solo show of her painting was organized during her lifetime, but she took part in several group exhibitions, including the one held by the Association of Croatian Artists in Zagreb in 1898, the Austro-Hungarian Exhibition in St. Petersburg and Moscow in 1900, and the World Fair in Paris in 1901. A retrospective show of her work was not organized until 1957, to mark the 50^th anniversary of her death, by the Institute of Fine Arts of the Yugoslav Academy of Zagreb. In 2008, the Klovićevi Dvori gallery in Zagreb paid a tribute to her. Raškaj’s landscapes are regarded by the critics as the high point of Croatian watercolour art, in particular those painted in about 1900 in a dreamlike and impressionist style.