Sentimentalism is usually studied through US-British relations after the American Revolution or in connection to national reforms like the abolitionist movement. instead argues that African American, Native American, Latinx, and Anglo American women writers also used sentimentalism to construct narratives that reframed or countered the violence dominating the nineteenth-century Americas, including the Haitian Revolution, Indian Removal, the US-Mexican War, and Cuba's independence wars. By tracking the transformation of sentimentalism as the US reacted to, enacted, and intervened in conflict demonstrates how marginalized writers negotiated hemispheric encounters amidst the gendered, racialized, and cultural violence of the nineteenth-century Americas. It remaps sentiment's familiar transatlantic and national scholarly frameworks through authors such as Leonora Sansay and Mary Peabody Mann, and considers how authors including John Rollin Ridge, John S. and Harriet Jacobs, María Amparo Ruiz de Burton, Victor Séjour, and Martin R. Delany adapted the mode. Transamerican sentimentalism cannot unseat the violence of the nineteenth-century Americas, but it does produce other potential outcomes-including new paradigms for understanding the coquette, a locally successful informal diplomacy, and motivations for violent slave revolt. Such transformations mark not sentiment's failures or distortions, but its adaptive attempts to survive and thrive.