Douglas was born in 1890 to William and Grace Galbraith at Barry Road, Camberwell, London. His father was Merchant Bank manger. Douglas studied medicine becoming a Dr. He enlisted with the Royal Army Medical Corps during the First World War as a Second Lieutenant gaining promotion to Captain. He was awarded the M.M. For conspicuous gallantry and devotion to duty whilst serving in Mesopotamia in 1919. He was wounded in the head whilst attending to a wounded officer, and though in great pain, continued to carry out his duties for the remainder of the day with zeal and determination.
In 1923 he married Hannah Bowen Jones, the daughter of a farmer and manufacturer of Welsh blankets, at Bromley, Kent and they moved to Launceston. They had a son Hugh James b. 1924. He joined the practice of Dr’s. Thompson and Gibson at the Southgate surgery and they resided at ‘Culcreuch’ Dunheved Road. His wife took an active role within the public life of Launceston first as Matron of the Launceston Infirmary and later as a Justice of the Peace.
Douglas passed away at Launceston Hospital on March 8th,1959 at the age of 69. In his will, he left a total of £20,677.