[1][2][3][4] His father, either named Dumitru or Anastasie Demian,[4][5] was a bank manager who had been temporarily relocated to Budapest for work,[4][3] and his mother was Maria Stoia, from Lipova.

His father supported his pursuits, sending his son's drawings to various Austro-Hungarian magazines, and even renting a store window in Timișoara to display his artwork to the public.

[4] While in Paris, he worked under Maurice Denis as part of the Ateliers d'Art Sacré, a mainly-Catholic artist's collective devoted to creating modern religious art.

[7] Though based in France until 1925, Demian contributed art and illustrations to a number of Romanian publications, including the Cluj-based literary-cultural magazines Gândirea and Erdélyi Helikon, and the Timișoara-based Vremea and Luceafărul.

[16] After World War II, Demian continued to contribute illustrations to books (especially children's literature and volumes of poetry), including a translation of the Nibelungenlied by Adrian Maniu,[17] and an illustrated edition of Vasile Alecsandri's Poezii populare ale românilor ("Popular poetry of the Romanians"),[18] and volumes of work by Lucian Blaga, Emil Isac, Octavian Breazu, Sabin Drăgoi, Mihail Sadoveanu, Ion Creangă, and Radu Boureanu.