Low's work is remarkably free from the conventional devices of the professional cartoonist, and in his drawings of celebrities in various walks of life, which appeared in the New Statesman, he showed a gift for genially humorous portraiture. During the 1930s and 1940s, his appeals to national sentiment were founded on an understanding of the principal political figures of the period, from Churchill, Baldwin, and Chamberlain to Mussolini, Hitler and Goering. He was particularly critical of British Conservative supporters of appeasement.

Born at Dunedin, New Zealand, he worked for various New Zealand papers until 1911, when he joined the staff of the Bulletin in Sydney, New South Wales, Australia. He went to London in 1919 to work on the Star, at the suggestion of the novelist Arnold Bennett, and became as celebrated for his portraits of Lloyd George. He left the Star for the Evening Standard in 1927, and moved to the Daily Herald in 1950. In 1953 he became political cartoonist of the Manchester Guardian (now the Guardian), where he remained until his death. He published collections of his cartoons, including The New Rake's Progress (1934), Years of Wrath (1949), Low's Company (1952), and The Fearful Fifties (1960).