Skip Navigation

William George MacCallum

Portrait of William George MacCallum
William George MacCallum
Date: 1942
Medium: Oil on canvas
Dimensions: 43.5 x 33.5 in.
Make a Request

Tell Us More

Can you tell us more about this person? Have you spotted an error? Is there information missing? If you have new information to share, please complete the form below.

William George MacCallum


MacCallum, a former chairman of pathology at Johns Hopkins, was born in Dunnville, Ontario. He received a B.A from the University of Toronto in 1894. A member of the first graduating class of the Johns Hopkins University School of Medicine, he received his M.D. in 1897.

MacCallum spent a year as an intern at The Johns Hopkins Hospital and then became assistant resident in pathology under William Welch. In 1900, he went to Germany to work in the laboratory of Prof. Marchand in Leipzig. After his return to Baltimore in 1901, MacCallum was made resident pathologist at Johns Hopkins, then associate professor of pathology. In 1908, he was promoted to the position of professor of pathological physiology, a chair create especially for him.

From 1909 to 1917, MacCallum served as professor of pathology at the College of Physicians and Surgeons of Columbia University and pathologist to the Presbyterian Hospital of New York. He then returned to Johns Hopkins as professor and chairman of the Department of Pathology, a position he held until his retirement in 1943.

His research covered a wide variety of subjects; his most notable contributions were those relating to malaria and the function of the parathyroid gland. He traveled extensively and used his trips to broaden his knowledge of pathological anatomy. He wrote the definitive Textbook of Pathology and 173 articles, as well as biographical sketches and studies in the history of medicine.