Fredrick Willius, American cardiologist and author (died 1972)

Dr. Fredrick Arthur Willius was an American cardiologist and medical historian. He earned both his Bachelor of Science and Doctor of Medicine degrees from the University of Minnesota before joining the Mayo Clinic in 1917. At Mayo, Willius collaborated with Henry Stanley Plummer, through whom he was introduced to the emerging field of electrocardiography. This area would become central to Willius’s professional contributions.