Nobel laureate James Tobin said about him: "For the economics profession throughout the world, the third quarter of this century was an Age of Johnson.

He was born on 26 May 1923 in Toronto, Ontario, Canada, the elder son of two children of Henry Herbert Johnson, newspaperman and later secretary of the Liberal Party of Ontario, and his wife, Frances Lily Muat, lecturer in child psychology at the Institute of Child Study of the University of Toronto.

"[4] He graduated in 1943 and subsequently became, for one year, acting professor and sole member of the economics staff at St Francis Xavier University, in Antigonish, Nova Scotia.

"In 1944", explains Corden, "Johnson volunteered for active service in the Canadian armed forces and, after training, was sent to England in 1945, eventually doing clerical work in Canada House.

"[4] This was then followed by further study at Jesus College, Cambridge, where he obtained a first-class BA degree in economics under the tutelage of the Marxist economist Maurice Dobb; a return to the University of Toronto, where he earned his MA degree; and then finally doctoral research at Harvard University, where he completed the course work requirements in three terms.

He also held a visiting professorship at Queen's University in Kingston, Ontario and he briefly was professor at the Graduate Institute of International Studies in Geneva until his death.

This travelling style began in the fifties when he was teaching refresher courses for economists in Karachi and Singapore.

Economist Jagdish Bhagwati, writing about Johnson's productivity and accessibility, said, "Countless numbers of manuscripts would reach him, from aspiring students of international economics and somehow Harry found the energy and time to read them carefully and write back to the authors promptly.

The enormous admiration and affection for Johnson was reflected in the numerous obituaries by members of the economics profession that appeared soon afterwards.

Johnson made many contributions to the development of Hecksher-Ohlin theory and until the 1970s according to Moggeridge, was the second most quoted trade theorist after Paul Samuelson.

Despite being perhaps the most prolific economist of the modern era, Johnson's star has waned as is evidenced by the significant fall (discussed in Moggeridge's biography) in citations to his work in the past decade.

He retained a lifelong interest in Canadian politics and was heavily critical of nationalist and interventionist policies that prevailed at his time.