BEFORE THE CIVIL WAR In conjunction with its exhibit “New York Divided: Slavery and the Civil War,” the New-York Historical Society presents a panel discussion on the Dred Scott Supreme Court case that eventually led the country to civil war. Panelists include the author of “Two Men Before the Storm” (Greenleaf), Gregory Wallance, and a professor of English literature at the University of Maryland, Carla Peterson. Tuesday, 6:30 p.m., New-York Historical Society, 170 Central Park West at 77th Street, 212-873-3400, $15 general, $10 students, teachers, and seniors, $8 members.