John Fergus was educated at the University of Glasgow where he graduated MA in 1833, MB, CM in 1888 and MD in 1897. He spent much of his professional career as a physician to the Glasgow Royal Infirmary.

Freeland Fergus was part of a prominent medical family, his father being Dr Andrew Fergus and his brother being Andrew Freeland Fergus.

He served as President of the Royal Faculty of Physicians and Surgeons of Glasgow from 1929 to 1931.]]>