Stewart was born in Greenock, Scotland and served in the British Army during World War I. He then emigrated to New Zealand when he was 24. He later gained employment on the Auckland Transport Board as a clerk. During World War II he joined the military and was given a staff job as his medical grading prevented him from going abroad. At the end of 1942 he was released from service.
Political career
In 1935 he was elected to the Auckland City Council on a Labour Party ticket where he was chairman of the Library Committee. In both 1933 and 1938 Stewart was defeated standing for the City Council. He was also a member of the Auckland and Suburban Drainage Board. In both the 1950 and 1956local elections as well as a 1957 by-election he was the Labour Party's candidate for the Auckland mayoralty, placing second, third and second respectively. Stewart was present as a delegate at the 1940 Labour Party Annual Conference. Whilst in attendance Stewart seconded MP Bill Schramm's successful motion to expel John A. Lee from the party. Later that year he stood for the Labour nomination at the Auckland West by-election following the death of Prime MinisterMichael Joseph Savage, but lost to Peter Carr. Stewart then became chair of the Tamaki electorate committee and later Vice-President of the Auckland Labour Representation Committee.
Member of Parliament
Stewart was selected as the official Labour candidate for in the scheduled 1941 general election. He later contested the electorate in the, but lost to Clifton Webb. He then contested in unsuccessfully. He then represented the Arch Hill electorate from to 1954 following the retirement of Bill Parry. The electorate was then absorbed into neighbouring electorates, and he was defeated in, standing for Eden. Stewart was first on election night, with a provisional lead of 172, but after the 1,300 postal votes were counted he lost by a mere 8 votes to National's Duncan Rae.
After leaving parliament he returned to work as a clerk at the Auckland City Council until he retired in 1966. He died on 5 February 1973. He was survived by his wife and two sons.