[2] Architecture projects were put on hold when Canada entered World War II, so Mayerovitch turned his attention to painting, with one painting, a war-themed work entitled Home Front, exhibited at the Montreal Museum of Fine Arts.

This work garnered praise from Ottawa Journal critic Robert Ayer, which in turn caught the attention of National Film Board of Canada (NFB) founder John Grierson, who appointed Mayerovitch artistic director of the NFB's Wartime Information Board's Graphic Arts Division—even though Mayerovitch had never designed posters before.

From 1942 to 1944, Mayerovitch produced World War II propaganda posters, using the artist's signature "Mayo.

"[2] Following the war, Mayerovitch resumed work as an architect and became active in urban planning.

In 2000, his 90th birthday was marked with the planting of a magnolia tree in the school of architecture's Centennial Garden.