Brittain was born and raised in Saint John and is among the country's most accomplished painters. He studied art with Elizabeth Russell Holt in Saint John and under Harry Wickey in New York City. In 1932, after living in New York, he returned to Saint John, where he worked at clerical and construction jobs and opened an art studio on the waterfront. During this period, he captured realistic scenes of everyday life in the city which incorporated social commentary. Brittain served with the Royal Canadian Air Force during World War II and served two years as a war artist.
After studying in New York, Brittain felt he didn't have to leave the region to make a career as an artist. However, at the time Saint John was still recovering from three major fires and was in the middle of the Depression. As a young man he worked as a draftsman and worked on the docks while working on his craft amongst a thriving arts community including Ruth Starr, Ted Campbell, Fred Ross and Jack Humphrey. In January 1949, his first major exhibit at the New Brunswick Museum in Saint John. The exhibition was so popular he went on to do a series of solo shows in New York. In 1968, Brittain was awarded the Canadian Centennial Medal for his contribution to Canadian art.
Brittain is considered one of Canada's most prolific painters. His work broke from contemporary style at the time of the Group of Seven when landscapes of the country dominated Canada's art scene. Brittain focused on working class life in his hometown of Saint John with his signature style in social-realism.