Theo van Doesburg was a Dutch artist, who practiced painting, writing, poetry and architecture. He is best known as the founder and leader of De Stijl, Theo van Doesburg was born Christian Emil Marie Küpper on August 30,1883, in Utrecht, the Netherlands, as the son of the photographer Wilhelm Küpper and Henrietta Catherina Margadant. After a short training in acting and singing he decided to become a painter and he always regarded his stepfather, Theodorus Doesburg, to be his natural father, so that his first works are signed with Theo Doesburg, to which he later added the insertion van. His first exhibition was in 1908, from 1912 onwards, he supported his works by writing for magazines. This suddenly changed in 1913 after reading Wassily Kandinskys Rückblicke, in which he looks back at his life as a painter from 1903–1913. It made him realize there was a higher, more level in painting that originates from the mind rather than from everyday life. It was already in 1912 that Van Doesburg was criticizing Futurism in an art article in Eenheid no. 127, on November 9,1912, because The mimetic expression of velocity is diametrically opposed to the character of painting, on November 6,1915, he wrote in the same journal, Mondrian realizes the importance of line. The line has almost become a work of art in itself, the white canvas is almost solemn. Each superfluous line, each wrongly placed line, any color placed without veneration or care, can spoil everything—that is, Van Doesburg saw in these paintings his ideal in painting, a complete abstraction of reality. Soon after the exposition Van Doesburg got in contact with Mondrian, and together with related artists Bart van der Leck, Anthony Kok, Vilmos Huszar, oud they founded the magazine De Stijl in 1917. Although De Stijl was made up of members, Van Doesburg was the ambassador of the movement. He moved to Weimar in 1922, deciding to make an impression on the Bauhaus principal, Walter Gropius, while Gropius accepted many of the precepts of contemporary art movements he did not feel that Doesburg should become a Bauhaus master. Doesburg then installed himself near to the Bauhaus buildings and started to attract students interested in the new ideas of Constructivism. The friendship between Van Doesburg and Mondrian remained strong in these years, although their way of communication was by letter. In 1923 Van Doesburg moved to Paris together with his later wife Nelly van Moorsel, because the two men got to see each other on a much more regular basis the differences in character became apparent, Mondrian was an introvert, while van Doesburg was more flamboyant and extravagant. During 1924 the two men had disagreements, which led to a split in the same year. Mondrian accepted some concepts of diagonals, such as in his Lozenge paintings, in recent years, however, this theory gained critique from art historians such as Carel Blotkamp, who cites their different concepts about space and time as the main reason for the split
Theo van Doesburg as Sergeant Küpper. c 1915.
Theo van Doesburg, Composition in Gray (Rag-time), 1919, Oil on canvas, 196.5 × 59.1 cm (38 × 23.3 in), The Solomon R. Guggenheim Foundation Peggy Guggenheim Collection, Venice, 1976