The son of a wine merchant, Rudolf Maeglin grew up in upper middle-class circumstances in Basel. His mother came from a wealthy family of silk industrialists. After graduating from high school he began to study medicine, which he completed with the state examination in 1918. For a short time he worked as an assistant doctor at the Cantonal Hospital in Geneva before he decided to pursue a career as a freelance artist and gave up the medical profession in 1919. After a trip to Italy in 1921, he lived in Paris from 1922-27, where he attended the academies Grande Chaumière and Colarossi. Study trips to Brittany in 1923 and 1925 and to Spain and the Balearic Islands in 1926-27. 1927 he returned to Basel, where until 1936, he worked as a hired hand on construction sites and as an unskilled worker in factories of the chemical industry during the day. In this working world he found the pictorial themes with which he would henceforth exclusively deal. In 1933 he was one of the founding members of Group 33 and subsequently participated in its most important exhibitions. From 1936 he lived as a freelance painter and graphic artist. He devoted himself mainly to woodcuts and later became a member of the Xylon Association. The architect Ernst Egeler, a friend of Group 33, built a simple studio house for him in 1947 in the working-class district of Kleinhüningen, where he lived until his death. After 1960, the deterioration of his health forced him to give up painting outdoors. In 1966-68, he was commissioned by the Basler Kunstkredit to create three stained glass windows for the staircase of the cantonal employment office on Utengasse in Basle. His work was honoured by the Kunsthalle Basel in 1970 in a double exhibition with Paul Camenisch and by the Kunsthaus Zug in 2012 with a major solo exhibition.

Maeglin laid the foundation for his personal style during the Parisian period 1922-27, which matured without abrupt changes from the 1930s onwards. Through his engagement with the naive painting of France and German Expressionism, he arrived at a simplified drawing, which fixes the pictorial space on a clearly organized, parallel-perspective framework of lines and rhythms through strong color contrasts and fine chromatic gradations. After returning to his home town in 1927, his artistic interest focused on the world of construction sites and chemical factories with the people working there, who had become familiar to him as fellow workers. In his late work after 1960, the examination of the professional and living situation of the workers and their families is expressed in forceful, mostly strictly frontal portraits. Through his superficially naive portrayal of what he saw, without pathos or sentimentality, Maeglin created an independent work that stands out from the thematically related paintings of socialist realism and is close to the working-class paintings of Fernand Léger. The translation of pictorial motifs into the medium of the woodcut refers to the close relationship between his painted and graphic work.

Due to his thematic limitation, he has become an outsider artist, whose importance within Group 33 was recognised only late. His paintings, which depict the gradual transformation of Basel through the great buildings, are culturally and historically significant testimonies to the city's more recent architectural history.

Silvan Faessler, 1998, updated 2016