The German painter and social reformer Karl Wilhelm Diefenbach was born in Hadamar, Hesse, in 1851. His father was the painter and drawing teacher Leonhard Diefenbach from whom he received first lessons in art. Initially Karl Wilhelm Diefenbach earned a living as a design draftsman for a railroad construction office and worked for various photo studios. In 1872 he went to Munich where he was active as a freelancer for the photography publishing house Hanfstaengel, the same year he also began to study at he Academy of Fine Arts, Munich. In 1873 Karl Wilhelm Diefenbach was severely ill with typhus, as a consequence of his illness he developed an interest in alternative ways of life and thinking, he also had visionary experience and joined a non-denominational community. The artist repeatedly came into conflict with his social surroundings and local authorities because of his odd character, his missionary intentness and his overall unusual lifestyle.
In 1885 Karl Wilhelm Diefenbach founded the alternative community Humanitasin an abandoned stone pit at Höllriegelskreuth south of Munich. In 1887 the young artist Hugo Höppener, whom Diefenbach would call Fidus, also joined the community. Later Höppener adopted Fidus as his artist name. In 1892 Karl Wilhelm Diefenbach followed an invitation of the Autrian Kunstverein and relocated to Vienna with his family and other members of his life reform community. In Vienna his work was met with great approval. Together with Fidus he created the monumental 68 meter long silhouette frieze Per aspera ad astra in 1892, today it is considered his main work.
In 1897 Karl Wilhelm Diefenbach founded the commune Himmelhof. Despite several exhibitions, the artist was not successful commercially, in 1899 his commune even had to file bankruptcy. In 1900 Diefenbach traveled to Italy and settled on the island of Capri. For a small fee he showed visitors the exhibition of his symbolist landscape paintings in his studio and explained his life reform concepts. Karl Wilhelm Diefenbach died on Capri in 1913.
After years in oblivion the life and work of Karl Wilhelm Diefenbach was honored in a successful exhibition at Villa Stuck in Munich in 2009. The exhibition was also mounted at the Hermesvilla in Vienna in 2011.