The Medford Historical Society & Museum presents a talk at the library with historian Stephen Puleo about his new book, “The Great Abolitionist: Charles Sumner and the Fight for a More Perfect Union,” the story of one of the most influential non-presidents in American history. In the tempestuous mid-19th century, as slavery consumed congressional debate and America careened toward civil war and split apart — when the very future of the nation hung in the balance — Charles Sumner’s voice rang strongest, bravest, and most unwavering. Where others preached compromise and moderation, the Boston-born lawyer, politician, and statesman denounced slavery’s evils to all who would listen and demanded that it be wiped out of existence. More than any other person of his era, he blazed the trail on the country’s long, uneven, and ongoing journey toward realizing its full promise to become a more perfect union. Register through Eventbrite.