Complex sentence: Kurt Seligmann (1900-1962) was a Swiss-American Surrealist painter and engraver, known for depicting an imaginary world populated by medieval troubadors and jousting knights engaged in macabre rituals and executed with an expressive violence.
Split into simpler sentences: Kurt Seligmann (1900-1962) was a Swiss-American Surrealist painter and engraver. He was known for his fantastic imagery showing scenes of medieval troubadors and jousting knights engaged in macabre rituals, and often executed with an expressive violence.