Acclaimed scholar Edward Gray offers the first comprehensive history of the Mason-Dixon Line, a border at the center of early American political contestation. Formalized in 1767 to fully and finally demarcate Pennsylvania, Maryland, and Delaware, the Line resolved a longstanding jurisdictional conflict that had provoked bloodshed among colonists and ensnared Lenape and Susquehannock populations. In 1780, Pennsylvania’s Act for the Gradual Abolition of Slavery inaugurated a new phase, as the Line became a boundary between free and slave states and their distinct legal regimes. Then, with the passage of the Fugitive Slave Act in 1850, the Line became a federal instrument to arrest freedom-seeking Blacks. Only with the end of the Civil War did the Line’s significance fade, though it haunted the geography of Jim Crow. Mason-Dixon tells the gripping story of colonial grandees, Native American diplomats, Quaker abolitionists, fugitives from slavery, capitalist railroad and canal builders, US presidents, Supreme Court justices, and Underground Railroad conductors-all contending with the relentless violence and political discord of a borderland that transformed American history.
