He was born on 3 November 1905 in Glasgow the son of Jeanie Lightbody and John Montgomery.
He attended Hillhead High School then studied medicine at the University of Glasgow graduating with an MB ChB in 1928.
In 1931 he began lecturing in clinical pathology at the University of St Andrews, also gaining a doctorate there (PhD) in 1937.
[2] In World War II he reached the rank of Brigadier in the Royal Army Medical Corps mainly serving in the Middle and Far East, in particular Burma.
His proposers were Norman Davidson, Robert Garry, Alexander Murray Drennan and Charles Wynford Parsons.