Within broad limits business law always has been instrumental to American economic development. J. Willard Hurst’s classic formulation characterized nineteenth-century law and the conditions of freedom as permitting a release of middle-class entrepreneurial energy. Elaborations of this idea stressed that law encouraged dynamic rather than traditional uses of property, often favoring capitalist exploitation of weaker groups. Emphasizing the importance of incentives in the operation of economic markets or political and legal systems, Douglass C. North recognized, by contrast, that imperfect information, transaction costs, and other factors brought about outcomes that often were neither optimal nor even beneficial to those who purportedly sought such results through manipulation of the rules of the game. Thus according to North, the institutional framework underlying the impressive economic growth of the nineteenth-century United States provided incentives for individual and group action that resulted in a mix of economically productive and adverse outcomes. Groups pursued contrary views of self-interest in part because ideological conflicts fostered opposing perceptions of property rights. Perhaps the most significant instance in which interest-group and ideological struggle followed an unpredictable course was the clash between Democrats and Republicans that culminated in the Civil War. Yet to a certain extent, in the nineteenth-century American economy such clashes were endemic.