[1] His father Hamish, a captain in the Second Australian Imperial Force, 2/19th Battalion, was killed in the Fall of Singapore on 19 January 1942, leaving three children — Ranald and two sisters, Jean and Morna.

Macdonald greatly admired his Headmaster, Sir James Darling, who initiated Timbertop and gave the eulogy at his grandfather Oswald Syme's funeral.

Macdonald had scribbled his details on the back of their scorecard, which resulted in him attending Columbia on scholarship to study a combined business and journalism Master of Science degree (1963–64), the first of its kind in the United States.

In his early years at The Age, Macdonald rebuffed takeover bids by, among others, Frank Packer, his own cousin Rupert Murdoch, and The Times owner Roy Thomson.

To maintain the newspaper's independence, Macdonald created the Syme-Fairfax Partnership with John Fairfax & Sons, which allowed the Syme Trust to continue after Oswald's death in 1967.

Macdonald and Perkin guided the paper through a transformation from its staid, conservative roots to what news magazine The Bulletin called "Australia's Most Important Newspaper".

Macdonald's tenure saw sweeping changes at The Age, including the addition of bylines to stories and the introduction of columnists, such as highly respected Phillip Adams.

Macdonald and Perkin introduced talented cartoonists to readers of The Age, including Les Tanner, Ron Tandberg, Bruce Petty, Michael Leunig, John Spooner and Peter Nicholson.

[7] In 1981, Macdonald prodded the Victorian Government to establish the Norris Inquiry into press ownership in Victoria, as he believed that a significant investment by John Fairfax & Sons in the Herald and Weekly Times group, the Melbourne-based rival of The Age, created a conflict of interest.

In 1999, Macdonald accepted the position of Boston University's international programme in London, where he helped to establish new overseas study programs in Auckland and Sydney.

He co-founded the European Study Abroad Program (EUSA), a company which organises internships for thousands of American students a year in Dublin, Grenoble, Madrid, Paris, Sydney, London, Los Angeles and Boston.

Before leaving The Age, Macdonald was appointed by Victorian Premier John Cain Jr. to chair Victoria's 150th Anniversary Board from 1982–85, which organised the yearlong activities.

In 1985, unsuccessful investments in a string of health clubs combined with an over-commitment to unpaid positions, led to financial troubles for Macdonald.