John Neil McCallum was born in Brisbane, Queensland, in 1918, son of theatre owner and entrepreneur John Neil McCallum Sr, who built and ran the 2000 seat Cremorne Theatre on the banks of the Brisbane River for many years. He was known as 'Jack' in his childhood. McCallum Jr was born during an opening night comedy performance and a friend sent his father a telegraph: 'Congratulations on two howling successes.'
McCallum Sr had migrated with his parents from Scotland and, on the early death of his father, he and his brother were brought up by their mother who continued to run the small farm that McCallum's grandfather had bought at Bald Hills. McCallum Sr became an accomplished musician and was soon involved in the Brisbane entertainment scene. John McCallum's childhood memories are full of backstage encounters at the Cremorne Theatre with the variety of performers peopling a multitude of hit shows and it was inevitable that he should enter the theatre as a profession. His mother was an accomplished amateur actress, born in England.
The middle child in this family of three boys, McCallum and his older brother received their primary school education in England. When the Great Depression forced the family to return to Australia, McCallum entered a Church of England Grammar School in Brisbane and 'liked it enormously'.
His early theatrical training was with Barbara Sisely at the Brisbane Repertory Company. He later did two years at RADA in London under Kenneth Barnes and his sisters Violet and Irene Vanburgh. From there he went into repertory at Tunbridge and Northampton. In 1939 he did a season at Stratford-upon-Avon playing small roles and understudying. From there he moved to similar roles at the Old Vic under Harley Granville-Barker in which he appeared in the historic 1939 production of King Lear that featured Jack Hawkins with Peggy Ashcroft, Fay Compton and Cathleen Nesbitt.
McCallum returned to Australia shortly afterwards in order to join the AIF for the duration of World War II, in which he served in New Guinea. After the war he joined the J. C. Williamson company for a while, working with Gladys Moncrieff in The Maid of the Mountains. Because there were limited theatrical choices in Australia at the time, McCallum returned to England where he soon went back into to films (he had already appeared in two movies before returning to Australia: Heritage 1935 and Held for Ransom 1938). He became an Australian leading man in films of the 1940s and 1950s. In 1948 he married the actress Googie Withers, with whom he appeared in a large number of films. McCallum has also written, directed and produced numerous films and television series, particularly the ground-breaking international TV series Skippy which he co-produced with Lee Robinson. McCallum has also widely acted on the stage. A particular favourite role was in The Circle by W. Somerset Maugham. He acted alongside his wife Googie in this production not only in Australia but also in the UK.
At the invitation of Sir Frank Tait of J. C. Williamsons, McCallum became joint managing director. McCallum was keen to encourage the casting of talented Australians in leading roles and was instrumental in beginning the starring careers of Kevin Colson, Jill Perryman, Nancye Hayes, Barbara Angell and others. His contribution to the Australian performing arts is considerable and, in 1971, he was made a Commander of the Order of the British Empire (CBE). In 1992, he was made an Officer of the Order of Australia (AO). Both honours were made for services to drama and theatre.