Western environmental thought and practice historically separated humans and nature. This dichotomy led to an ecological bias in environmental research and management, but increasingly issues like biological invasions are being re-conceived as socioecological problems. Here, we studied how terrestrial and freshwater vertebrate species assemblages in Tierra del Fuego (TDF) have been co-constructed between humans and nature. The social imaginary concept was used to integrate shared discourses (e.g., species preferences, nature ideals, broader social values) and practices (e.g., species introductions, environmental management) via institutions (e.g., informal norms, laws, governmental entities, organizations). To analyze how socio-historical processes interact with biological invasions, we used TDF as a case study linked to broader geographic scales in Patagonia, Argentina, Chile and beyond. We found three predominant social imaginaries characterizing human–nature relationships that led to 20 species being introduced and subsequent efforts to remove or control seven of these: Colonization (ca. 1850–1930), Development (ca. 1930–1980) and Conservation (ca. 1980–present). Each imaginary materialized via formal and informal institutions operating from local to international scales. Specifically, we uncovered 10 discourse categories that related to human interventions of TDF’s species assemblage, ranging from racism and nationalism (Colonization and Development, respectively) to wilderness and uniqueness (Conservation). These ideas affected actions to introduce (eight and 10 species during Colonization and Development, respectively) or remove species (one and seven in Development and Conservation, respectively). An integrated socio-ecological understanding of biological invasions identified not only social preferences and values, but also underlying social processes that can help resolve the complex and underappreciated interactions between society and biological invasions.