The journalist and editor was born in Middlesbrough. At the age of three Tyerman contracted polio and was paralysed from the neck down. For ten years he showed extraordinary courage and eventually regained control of all parts of his body except that he always had to walk with splints. He therefore went late to school but passed through the Friends' school at Great Ayton, Coatham grammar school at Redcar, and Gateshead secondary school to Brasenose College, Oxford.
In 1936 Tyerman joined The Economist and throughout the Second World War he was one of the most influential journalists in England. He was deputy editor until 1944 but was quite often in charge of the paper. In 1943-4 he was also deputy editor of The Observer, frequently putting that paper to bed on the Saturday, having put The Economist to bed on the Thursday. Both papers played a major role in preparing the intellectual ground for Britain's post-war welfare state.
His friends hoped Tyerman would become editor of The Times but by now his physical immobility was sapping his boundless energy and was making it increasingly difficult for him to edit a daily newspaper. He eventually became editor of The Economist (1956-65).