William John Eccles (July 17, 1917 – October 2, 1998), commonly known as W. J. Eccles, was a historian of Canada.

Born in Thirsk, North Yorkshire, England, his family immigrated to Canada in the 1920s. He studied at McGill University under historian Edward Robert Adair and at the Sorbonne in Paris. His book Canada under Louis XIV is dedicated to E.R. Adair. In 1953, he joined the faculty at the University of Manitoba. Four years later, he joined the faculty at the University of Alberta. Then in 1963, he was appointed to a professorship at the University of Toronto. He retired from the University of Toronto in 1983.

In 1979, the Royal Society of Canada awarded him the J. B. Tyrrell Historical Medal for his contributions to the history of Canada.

He died in Toronto on October 2, 1998.

His papers are located in the libraries of McMaster University.