Fergus was educated at Glasgow University, where he took the M.A. in 1907, and the M.B. and B.Ch. in 1911. After he qualified he went to New Zealand, but returned to the UK when war broke out. He joined the R.A.M.C. on 18th January 1915. He drowned when the transport ship "Marquette" was torpedoed and sunk in the Aegean Sea. He was the son of John and Mary Young of "Fernbank", Kirkintilloch, Glasgow.