Macnaughten was born in 1872 in India before going to Wellington and the Hopetoun. He was a member of the XI and a prefect. He went to Woolwich where he won the sword of honour before being commissioned into the Gunners.
He served in India from 1894 to 1896, West Africa from 1898 to 1899, South Africa from 1900 to 1902, Somaliland from 1903 to 1904, India from 1905 to 1909, before returning to England. He was Major Instructor of Gunnery at the RH & RFA School of Gunnery at Shoeburyness in the run up to the war in which he served, being made a CMG and winning the DSO, the Croix de Guerre and eight Mentions. He was ADC to the King in 1920.
He resigned his commission as a Brigadier General and went to Shanghai to work with British American Tobacco. He became Chairman of the Shanghai Municipal Council, President of the United Services Association and the St Andrew’s Society.
He died a stone’s throw from College in Wokingham in 1948.