Thomas Grainger Stewart was born in Edinburgh and educated at Edinburgh High School. He obtained his MD from the University of Edinburgh in 1858 and undertook postgraduate study in Berlin, Prague and Vienna before becoming House Physician to Professor Laycock at the Royal Infirmary of Edinburgh. Early in his career he was appointed Lecturer on Materia Medica in the extramural school. On his appointment as Pathologist to the Royal Infirmary he became Lecturer on Pathology in place of Materia Medica.
