his active artistic life extended over more than 70 years, and throughout these years he was a controversial figure in danish art. willumsen was a co-founder of the rebellious artists' association den frie udstilling (the independent exhibition) in copenhagen in 1891.

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His active artistic life extended over more than 70 years, and throughout these years he was a controversial figure in Danish art. Willumsen was a co-founder of the rebellious artists' association Den Frie Udstilling (The Independent Exhibition) in Copenhagen in 1891.