Born on 16 August 1900, eldest son of James Greenwood of Blackburn, he served for two years in the Royal Flying Corps in the first world war. Afterwards he studied pharmacy in Blackburn Technical College, and by means of scholarships he worked his way at St Bartholomew's Hospital to study medicine.

Born at Royton near Oldham on 13 May 1903 the youngest of six children of a farmer who died the following year, he won his way to Hulme Grammar School with great determination in face of poverty. There he became captain of the cricket XI, and then went to Guy's Hospital where he served as demonstrat