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COLLECTION Identifier: H MS c174

William B. Castle papers


The William B. Castle papers, 1889-1991 (inclusive), 1925-1989 (bulk), consist of Castle's professional and personal correspondence, research records, personal and family papers, writings and publications, newspaper clippings, and assorted awards and honors.


  • 1889-1991 (inclusive),
  • Majority of material found within 1925-1989 .


Language of Materials

Records are in English.

Conditions Governing Access

Collection is open for research. Access requires advance notice. Access to Harvard University records is restricted for 50 years from the date of creation. These restrictions are noted where they appear in Series I. Access to personal and patient information is restricted for 80 years from the date of creation. These restrictions appear in Series I, II and III. Researchers may apply for access to restricted records. Consult Public Services for further information.

The Papers are stored offsite. Researchers are advised to contact Public Services for more information concerning retrieval of material.

Conditions Governing Use

The Harvard Medical Library does not hold copyright on all materials in the collection. Researchers are responsible for identifying and contacting any third-party copyright holders for permission to reproduce or publish. For more information on the Center's use, publication, and reproduction policies, view our Reproductions and Use Policy.


4.6 cubic feet (4 records center cartons, 1 document box, and 1 flat oversize box)

The William B. Castle papers, 1889-1991 (inclusive), 1925-1989 (bulk), consist of Castle's professional and personal correspondence, research records, personal and family papers, writings and publications, newspaper clippings, and assorted awards and honors. The collection contains four series. Series I, Professional Records, consists of professional correspondence, Harvard Medical School records, and research from Castle's 1931 expedition to Puerto Rico. Series II, Writings and Publications, contains articles, drafts, and unpublished writings. Series III, Personal Papers, contains personal correspondence, the personal papers of his father, William E. Castle, photographs, and newspaper clippings. Series IV consists of medals, awards, and honorary degrees received by Castle.

Materials are entirely in English.

Biographical Note

William B. Castle (1897-1990), M.D., 1921, Harvard Medical School, Boston, Massachusetts, was a leading hematologist, discovering gastric intrinsic factor and how its absence in human digestion leads to pernicious anemia. Castle served as Director of the Thorndike Memorial Laboratory at Boston City Hospital from 1948 to 1968 and as Professor of Medicine (1937-1957), George Richards Minot Professor (1957-1963), and Francis Weld Peabody Faculty Professor (1963-1968) at Harvard Medical School. After his retirement from Harvard Medical School in 1968, he held the position of Distinguished Physician in the Veterans Administration (VA) Hospital until his death in 1990.

William Bosworth Castle was born in Cambridge, Massachusetts on 21 October 1897 to William E. Castle (1867-1962), a professor of zoology at Harvard University, and Clara Sears Bosworth Castle (1870-1940). Castle attended Browne and Nicholas School in Cambridge, Massachusetts, and in 1914, entered Harvard College. At the end of his third year, Castle enrolled at Harvard Medical School and received his M.D. in 1921 without earning a bachelor’s degree, though he was elected to Phi Beta Kappa and Alpha Omega Alpha. Castle completed his internship with Massachusetts General Hospital, Boston, from 1921 to 1923.

Castle began his career at Boston City Hospital in Harvard Medical School's Thorndike Memorial Laboratory. It was there, in 1928, that he discovered the cause of pernicious anemia, then a fatal disease. Through experimentation, primarily on himself, Castle discovered that absence of the intrinsic factor in digestion did not allow patients to absorb much needed iron. Through this research, Castle also discovered that vitamin B-12 is a key ingredient for the treatment of pernicious anemia. In 1931, Castle led an expedition to Puerto Rico where he studied the diseases tropic sprue and anemia as Director of the Rockefeller Foundation Commission for the Study of Anemia in Puerto Rico. There, with Cornelius P. (Dusty) Rhoads, he introduced a new treatment for tropical sprue based upon his initial discoveries with iron and liver extract in pernicious anemia cases. In 1948, Castle became the third director of the Thorndike Memorial Laboratory, and in 1957, he was appointed to the George Richards Minot Professorship at Harvard Medical School; in 1962, a professorship was named in his honor. In 1963, Castle became the first Francis Weld Peabody Faculty Professor of Medicine, a position he held until his official retirement in 1968. That year, he became Distinguished Physician in the West Roxbury Veterans Administration Hospital, a position which he held until his death in 1990.

Castle received Honorary Degrees from Yale University, the University of Utrecht, the University of Chicago, Boston College, and the University of Pennsylvania. He was a Fellow of The American Academy of Arts and Sciences, as well as a Member of the National Academy of Science. In 1933, Castle married Louise Muller and moved with her to Brookline, Massachusetts. They had two children, Anne Castle Morris and William Rogers Castle. William B. Castle died on 9 August 1990.

Series and Subseries in the Collection

  1. I. Professional Records, 1910, 1921-1989
  2. ___ A. Harvard Records, 1921-1989
  3. ___ B. Puerto Rico Research Records, 1926-1986
  4. ___C. Correspondence, 1910, 1925-1988
  5. ______ 1. Professional Organizations, 1930-1987
  6. ______ 2. Chronological, 1910, 1925-1988
  7. II. Writings and Publications, 1925-1985
  8. III. Personal Papers, 1889-1991, undated
  9. ___A. Correspondence, 1929-1991
  10. ______ 1. Alphabetical, 1938-1991
  11. ______ 2. Chronological, 1929-1989
  12. ___ B. William E. Castle Papers, 1889-1987
  13. ___ C. Photographs, 1940-1948, 1979, undated
  14. ___ D. Clippings, 1942-1989, undated
  15. ___ E. “Quotable Quotes,” 1956-1989
  16. IV. Medals, Awards, and Honorary Degrees

Immediate Source of Acquisition

  1. Donated by Alan Collachico in November 2002. Accession number 2003-024.


  • Karnad, Anand B. Intrinsic factors : William Bosworth Castle and the development of hematology and clinical investigation at Boston City Hospital. Boston : Distributed by the Harvard University Press for the Francis A. Countway Library of Medicine, 1997.

Processing Information

Processed by Jessica Gleason and Bryan Sutherland, July 2011.

Processing staff in the Center for the History of Medicine analyzed, arranged, and described the records and created a finding aid to improve access to the collection. To enhance preservation, processing staff re-housed the collection and, where necessary, photocopied documents onto acid-free paper. Duplicate records and records that did not meet the collection policy of the Center for the History of Medicine were discarded. Folder titles were transcribed from the originals. Oversized items are housed in Box 5 and 6.

Castle, William B. (William Bosworth), 1897-. Papers, 1889-1991 (inclusive), 1925-1989 (bulk): Finding Aid.
Francis A. Countway Library of Medicine. Center for the History of Medicine.
Language of description

Repository Details

Part of the Center for the History of Medicine (Francis A. Countway Library of Medicine) Repository

The Center for the History of Medicine in the Francis A. Countway Library of Medicine is one of the world's leading resources for the study of the history of health and medicine. Our mission is to enable the history of medicine and public health to inform healthcare, the health sciences, and the societies in which they are embedded.

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