Race-based chattel slavery was the most contentious moral and political issue in the antebellum United States. The debates, and their stakes, confronted the one-hundred thousand Jewish immigrants of the1840-1850s almost upon arrival. This history honors thesis will study antebellum Jewish Orthodox reactions. It will situate the Orthodox debates within a broader set of disputes, including those of leading Protestant theologians along with recent and long-term Jewish history, such as European persecution, American assimilation, and the Jewish Enlightenment. This paper will highlight a key, but under-examined, moment in the development of American and post-Enlightenment Jewish thought. The author is indelibly grateful for the mentorship and encouragement of Professors Sarah Gordon and Kathy Peiss.