This dissertation examines sound as an epistemological category that challenges dominant historiographical discourses of national identity, depicting the Northeast region as a space of sociopolitical and cultural retrogression, alienated from Brazil’s modernity. Through case studies, this dissertation demonstrates how members of the Armorial Movement—a multifaceted artistic movement originating in the Northeast—articulated networks of cultural identity at the intersections of classical and popular music, literature, and grassroots politics. I argue that the Armorial Movement’s advocacy for a folk-oriented national aesthetic model, as opposed to the cosmopolitan views espoused by Tropicália and Mangue Beat, represents an undertheorized and marginalized dimension of Brazil’s negotiations with global modernity. This dissertation integrates archival research, ethnography, oral history, and media studies with critical methodologies from cultural anthropology, political theory, and race studies to offer a comprehensive cultural history of the Armorial Movement from its inception to the present. The interdisciplinary approach of this dissertation expands the inquiry beyond music, exploring power structures and the dynamics of social mobilization and dissent during periods of political upheaval.