Founded in 1824 in Philadelphia, the Historical Society of Pennsylvania is one of the oldest historical societies in the United States and holds many national treasures. The society's building, designed by Addison Hutton and listed on the City of Philadelphia's Register of Historical Places, houses some 600,000 printed items and over 19 million manuscript and graphic items.
The society is one of the largest family history libraries in the nation, has preeminent printed collections on Pennsylvania and regional history, and offers superb manuscript collections renowned for their strength in 17th-, 18th-, and 19th-century history. With the addition of the holdings of The Balch Institute for Ethnic Studies
in 2002 (and those of The Genealogical Society of Pennsylvania
in 2006 through a Strategic Alliance Agreement), the society has become a chief center for the documentation and study of the ethnic communities and immigrant experiences shared by people whose American history began more recently-between the late 19th century century and our own times. In 2009 HSP formally transferred ownership of its museum collection to the Atwater Kent Museum of Philadelphia.
Together these holdings, old and new, make the society one of the nation's most important special collections libraries--a center of historical documentation and study, education, and engagement.