The original collection of the Folgers centered on Shakespeare and English drama of his age. It consisted of rare books and manuscripts from the period as well as more recent writings, art, and ephemera related to Shakespeare and English drama. The latter category included prints, photographs, playbills, promptbooks, paintings, and reference books of many kinds.
From the beginning, the Folgers recognized that neither Shakespeare nor the English drama of his time could be studied in isolation. Therefore their holdings included numerous items bearing upon Renaissance English culture and civilization more generally and tracing the interpretation of Shakespearean drama to modern times.
The Folgers also turned to continental Europe for materials that influenced or reflected English thought and values, and made English culture in its various dimensions understandable in the larger context of Western European civilization.
Since the opening of the Folger Shakespeare Library in 1932, the collection has grown on the foundations laid by the Folgers themselves but has broadened in its comprehensiveness. The purchase of the Harmsworth collection in 1938 widened the focus to embrace all of English civilization from the beginning of printing to 1640.
Over the years, the field of acquisition was expanded to include all English books published between 1641 and 1700 as well as influential English books through the first quarter of the eighteenth century.
Dr. Louis B. Wright (Director, 1948–1968) also made substantial additions to the Folger's collection of Continental books and manuscripts dating from the Renaissance through the early modern period.
At the same time, the library began a concerted effort to strengthen the reference collection in realization that a dependence on the Library of Congress for such materials was inefficient and impractical. These additions allowed the Folger to become a major research library not only for the English Renaissance but also for the Renaissance generally and a prime source in this country for the study of the Italian Renaissance, the Reformation, early exploration, and for the great movements of drama, literature, history, and thought on the Continent in this period. As anticipated, these additions also enhanced the utility of the Library's English collection.