 During the First World war he served in the Royal Army Medical Corps

He was appointed to the Board of Control in 1931, replacing Arthur Rotherham as Medical Senior Commissioner

He was made a Companion of the Order of the Bath (CB) in 1950

He married Muriel Hodgson Jones in 1917; they had a son Frederick Douglas Rees-Thomas (1920-1995), and daughter Aelwyn Minette (1922-2012).He was widowed in 1934.In 1948 he remarried Ruth Darwin, a colleague of his on the Board of Control, daughter of Sir Horace and Lady Ida Darwin they had no children, and she died in 1972.