In 1888 Claus convinced Arthur Morren to enter his son at the Artesis Hogeschool Antwerpen but he left after a short time, disliking the conformist teaching methods.
[1] In 1888, he moved to Paris, where he frequented the studios of Alfred Roll, Pierre Puvis de Chavannes and Eugène Carrière.
Under the influence of Henry van de Velde, Morren made some works between 1890 and 1892, featuring closely and regularly spaced dots of contrasting color, conforming to pointillist theories of the French painter Georges Seurat.
[2] In the summer of 1892, eschewing the shortened painting process which was associated with Neo-Impressionism, he began to work in a more spontaneous manner, creating more space for emotions.
Influenced by the ideas of the United Kingdom of Great Britain and Ireland painters William Morris and Walter Crane, both advocates of applied art, he took part between 1893 and 1900 in the creation of jewelry, articles of daily use, wallpaper, etc.
He was active in the Atelier of French painters Alfred Philippe Roll, Eugène Carrière, Pierre Puvis de Chavannes and Henri Gervex.
After three years in Paris he returned to Antwerp where he participated in several avant-garde groups, particularly Als ik Kan, L’Association pour l’Art, La Libre Esthétique and Eenigen.
Contributing to Luminism he reached the summit of his second major artistic period between 1904 and 1907 ( Le mois des roses et L'été ) which ended on the eve of the World War I.
More emphasis was placed on the aesthetics of the transient with constantly changing color variations ( Le bâton de rouge , 1941).