[2] Haworth married Zema Barbara Cogill (1900–1988), a painter from South Africa who also studied at the Royal College of Art under Rothenstein.

[4] She says of him in her autobiography, "Peter Haworth was a young, good-looking, curly-headed autocrat, who was gradually transforming a mediocre secondary-school art department into a dynamic powerhouse.

[3] After the outbreak of war the Hawarths were both commissioned by the Canadian government to record the activities of the armed forces on the coast of British Columbia.

[2] In the period before World War II the Haworths would take the train from Toronto to make long visits in the summer to the region of Baie-Saint-Paul and Saint-Urbain in Quebec, as did many other Canadian and American artists.

On one such trip, just after the war, Doris McCarthy and three friends shared the same pension and painted with the Haworths, the start of an important friendship.

A review in the Vancouver Province in January 1944 said,[2] Mindful of the picturesque and strong nature of the western landscape, and introducing even typical local touches such as totem poles, the artists have vigorously portrayed a region guarded by planes, guns and ships ...

[2] The Canadian sculptor Elizabeth Wyn Wood gave a speech on "Handicrafts in Relation to Community Art Centres in Canada".

[11] Melwyn Breen of the Toronto Saturday Night wrote in 1952, We found Mr. Haworth in his study surrounded by the tools and materials of his work: samples of stained glass, stack of exquisite, jewel-like and meticulously painted sketches, huge 'cartoons', which are the blueprints for a finished window .

For the steps in the designs he has done for many churches in Toronto, Montreal, Ottawa, Hamilton and elsewhere, Haworth and his assistant Miss Gladys Allen, first make a water-color or tempera sketch of the finished window.

The cartoon is then taken to the firm that does the actual glass-making and assembling, and, under Haworth's supervision, the glass sections in the design are keyed to show the color and shape of the piece of glass to be used...[2] Hugh Thomson of the Toronto Daily Star wrote of his 1959 show at the Robert Gallery, There is no attempt at bold flourish and the bravura manner.