When Americans imagine their legal system, it is the adversarial trial--dominated by dueling larger-than-life lawyers undertaking grand public performances--that first comes to mind. But as award-winning author Amalia Kessler reveals in this engrossing history, it was only in the turbulent decades before the Civil War that adversarialism became a defining American practice and ideology, displacing alternative, more judge-driven approaches to procedure. By drawing on a broad range of methods and sources--and by recovering neglected influences (including from Europe)--the author shows how the emergence of the American adversarial legal culture was a product not only of developments internal to law, but also of wider socioeconomic, political, and cultural debates over whether and how to undertake market regulation and pursue racial equality. As a result, adversarialism came to play a key role in defining American legal institutions and practices, as well as national identity.