[1][3] Thomas Main was born on 25 February 1911 in Johannesburg, where his father was a mine manager who had emigrated there from England.
At the start of World War I his mother returned to England with Thomas and his two sisters Isabella and Mary, while his father joined the South African Army.
Main was educated at the Royal Grammar School, Newcastle-upon-Tyne before studying medicine at Durham University, graduating in 1933 and becoming a doctor in 1938.
After the war Main joined the Cassel Hospital, as medical director in 1946 and continued working there for the next thirty years.
[4] Training as a psychoanalyst under Michael Balint, he was supervised by Anna Freud, Melanie Klein and Paula Heimann.