This paper explains that A.M. Cassandre was a graphic designer and a typographer. It also explains that he was genuinely a creative artist. He was an inventor with a subversive streak and an aversion to academia and systems, but at the same time, he loved classical art history and wanted to be a painter.
From the Paper:
"Cassandre began his career with poster making, as he is most known for, in the hopes that he could become financially independent from his family. Immediately he began to apply a structuralism to his work that to this day allows us to think of him more as a designer than a minor illustrator or painter, and in general significantly defined the role of the designer."