Donald Grant Creighton was a Canadian historian whose major works include The Commercial Empire of the St-Lawrence, 1760–1850, a detailed study on the growth of the English merchant class in relation to the St Lawrence River in Canada. His biography of John A. Macdonald, published into two parts between 1952 and 1955, was considered by many Canadian historians as re-establishing biographies as a proper form of historical research in Canada. By the 1960s Creighton began to move towards a more general history of Canada.