The Lyman Family Papers consists of account books, diaries, letterbooks, newspaper clippings, writings, and scrapbooks of many generations of this illustrious New England family.

The largest portion of the collection contains chiefly the papers of Theodore Lyman, Jr. (1792-1849), author, philanthropist, and mayor of Boston, and Theodore Lyman III (1833-1897), zoologist, Civil War aide-de-camp to Union General George Gordon Meade, and Massachusetts congressman. Civil War scholars and historians will find particularly rich resources through vivid descriptions of military life, sketches of historical figures including Ulysses S. Grant, Abraham Lincoln, and Robert E. Lee, as well as Civil War diaries and newspaper clippings.

In addition, other Lyman family members and members of the related Shaw, Russell, Agassiz, and Eliot families are represented in the collection, providing genealogical sources on prominent Bostonians during the 18th, 19th, and 20th centuries.