Bertram Brooker came to Canada from England with his family in 1905, settling in Portage la Prairie in Manitoba. In 1921 he moved to Toronto, where he worked as a magazine editor. He joined the Arts and Letters Club, meeting Group of Seven members, in particular Lawren Harris, who introduced Brooker to his beliefs concerning the importance of spiritualism in art and to the theories of Wassily Kandinsky. The idea of music resonated in Kandinsky's abstract painting, and he considered colours to be like chords. This resonated with Brooker, as reflected in titles of his works such as Abstraction - Music. By 1926, Brooker was painting seriously, and had become a pioneer in abstraction in Canada. By 1927 he had his first exhibition, showing his abstract works at the Arts and Letters Club, then at the Group of Seven's 1928 exhibition. Considered radical and challenging in the late 1920s, the power of Brooker's abstract paintings gathered respect and renown over time. The National Gallery of Canada subsequently acquired his canvases Ascending Forms, Evolution and Alleluiah, all from the late 1920s. Other museums such as the Winnipeg Art Gallery, the Art Gallery of Ontario and the Vancouver Art Gallery have collected abstract work from this period.

After encountering Group artist Lemoine FitzGerald in Winnipeg in 1929, Brooker abandoned abstraction in favour of realism. He then produced nudes, portraits, still lifes and landscapes, with approaches ranging from a stylized realism to the use of elements of Cubism. Like Edwin Holgate, he encountered the controversial reactions to nudes that took place in the 1920s and 1930s in Toronto. In the 1930s, Brooker was working for the Toronto advertising firm J.J. Gibbons, but in 1934 took more time off to paint, and the subsequent few years were very productive. His work from this period was realistic, dynamic, harmonious in palette and had strongly defined form and volume. A founding member of the Canadian Group of Painters, he participated in their first exhibition in 1933.

Also a well known writer, Brooker wrote a syndicated column The Seven Arts, in which he critically reviewed theatre, music, visual arts and poetry. A group of his poems from the 1920s and 1930s was published in the book Sounds Assembling: The Poetry of Bertram Brooker, and he was awarded the first Governor General's Literary Award for his 1936 novel Think of the Earth.

Brooker joined the MacLaren Advertising Company in 1940, and by his retirement had attained the position of vice-president. He continued to paint both stylized and naturalistic landscapes. He died in Toronto in 1955.