Born in Montreal in 1878, William Willoughby Francis earned his medical degree from Johns Hopkins University in Baltimore in 1902. After interning at Montreal's Royal Victoria Hospital and spending some time in Europe to pursue postgraduate studies, Francis came back to Montreal where he opened a practice in 1906. He later became editor of the Canadian Medical Association Journal, then Registrar of the No.3 Canadian General Hospital in France during the First World War. When his second cousin Sir William Osler died in 1919, he donated his library to McGill University. Francis co-edited the catalogue of Sir William Osler's library, the Bibliotheca Osleriana, and ran the Osler Library of the History of Medicine until his death in 1959.