Salmon Portland Chase emerged over the course of his career as one of the most effective antislavery advocates in pre–Civil War politics. Driven by a desire for high office that even his allies found unnerving, Chase served as U.S. senator, governor of Ohio, U.S. treasury secretary, and, finally, as chief justice of the United States. Along the way, however, Chase consistently advocated for the cause of abolition and racial equality in the United States. He appeared on the national scene in the 1840s as a leader of the antislavery Liberty Party and a lawyer for fugitive slaves and the people who harbored them. In the 1840s and 1850s he articulated an influential narrative portraying the Constitution as a fundamentally antislavery document that had been distorted by a corrupt Slave Power. This narrative became part of the core of the new Republican Party’s ideology in the 1850s. Although he never managed to parley his influence into a presidential nomination, Chase maneuvered himself into positions where he could force his commitments to abolition and racial equality into the center of antebellum politics and beyond. In so doing, he helped transform antislavery from a marginal political force in the 1840s to a dominant (and successful) one by the 1860s.