The artist Anna Cassel (1860–1937) has until now been known for her paintings of magnificent natural views, landscapes and urban environments. However, the fact that her artistry also reflected spiritual beliefs and her involvement in, among other things, spiritualism and theosophy has not been noticed. Only now, nearly a century after her death, is Anna Cassel's significance for abstract and spiritual art beginning to shine through, not least thanks to her deep friendship and collaboration with fellow art