Henry Charles Lea (September 19, 1825 – October 24, 1909) was an American publisher, civic activist, philanthropist and historian from Philadelphia, Pennsylvania.
He took over the family publishing business from his father, Isaac Lea, and implemented several medical and scientific publications. The business operated under various names including Lea Brothers & Co., Lea & Febiger and Blanchard & Lea until his sons took over the business in 1880.
He promoted health projects including the Lea Laboratory of Hygiene at the University of Pennsylvania and the Pennsylvania Epileptic Hospital and Colony Farm. He organized the Citizens' Municipal Reform Association of Philadelphia to fight corruption in city government. He was a founding member of the Union League of Philadelphia during the American Civil War. He managed publications and supported their efforts for recruitment of Union Army soldiers, including African-Americans. He helped found the National Republican League to prevent a third U.S. presidential term for Ulysses S. Grant.
Lea wrote multiple books focused on church history, especially the Spanish Inquisition. He received honorary degrees from Harvard University, Princeton University, University of Giessen, University of Moscow, and University of Pennsylvania. He was a member of multiple learned societies and served as president of the American Historical Association in 1903.
