Influenced by Romanticism his painting is symbolist with mythological subjects often overlapping with the Pre-Raphaelites. His pictures portray mythological, fantastical figures along classical architecture constructions (often revealing an obsession with death) creating a strange, fantasy world.
The best known of his paintings, "The Isle Of The Dead" (of which there were 5 versions), inspired many other artists : H.R. Giger (also Swiss) did two paintings of it in hommage to Böcklin, Rachmaninoff wrote a symphonic poem (Op.29) about it...
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