David Lewis (1909–1981) was a Russian-born Canadian Rhodes Scholar, labour lawyer and social democratic politician. He was national secretary of the Co-operative Commonwealth Federation from 1936 to 1950. As the United Steelworkers of America’s legal counsel in Canada, he played a central role in the creation of the Canadian Labour Congress in 1956 and in the New Democratic Party (NDP)'s formation in 1961. In 1962, he was elected as a Member of Parliament. He was the NDP's leader from 1971 to 1975. After his defeat in the 1974 Canadian election, he retired from politics. He spent his last years as a university professor and a newspaper travel correspondent. In retirement, he was named to the highest level of the Order of Canada for his political service. After a lengthy battle with cancer, he died in 1981.