Hortense Mattice Gordon drew avidly as a child and had decided to become an artist by the time she was 16. She set up a studio on a 200 acre fruit farm owned by relatives near Chatham, Ontario, where in addition to creating her own work, taking lessons from respected Canadian landscape painter Alexander M. Fleming, and painting and selling china, she took in pupils. She entered a landscape work in the Royal Canadian Academy competition in 1916 and it was promptly accepted. When shown, it impressed John S. Gordon, who was then Director of the Art Department of the Hamilton Technical Institute. He sought out Gordon and was able to offer her a post at the school when one opened in 1918, which she accepted. They would marry in 1920, and Gordon would continue to teach at the school until 1951, succeeding her husband as head of the Art Department from 1930.

In the summers they travelled to Paris, Amsterdam, and New York regularly, and were exposed to European avant-garde artists, in particular the Barbizon School, which had a decided influence on Gordon's own approach to aspects of her art. They set up a summer studio in Paris, and while there, she worked in an Impressionist manner for a time, then explored the ideals of Cubism. In Canada, she followed the activities of the Group of Seven and the burgeoning movements in Canadian Modernism.

Beginning in 1930, her work became decidedly abstract. She trained under Abstract Expressionist Hans Hofmann in Cape Cod, Provincetown in summer of 1946, along with Alexandra Luke; they were among the first Canadian artists to do so. She would return in 1949, 1952 and 1954. From him, she learned the importance of dynamism in abstract works, and his theories were critical to her art. Known for her bright, bold abstract paintings, Gordon became a founding member of the Painters Eleven group, and exhibited in their opening show at Roberts Gallery in 1954. This would bring Gordon wide acclaim; she would go on to show in New York and Toronto as a result. She died in Hamilton in 1961, and was given a memorial retrospective in 1963 at the Art Gallery of Hamilton.