This study examines how transnational conditions of markets, societies and states empower civic groups, social movements, advocacy networks or resisters to participate in cause-oriented action that connects two or more polities. Preliminary theses infatuated with the latest and thickest wave of globalization have blown back into a solidified antithesis. Under this influential antithesis, international interactions between states create more opportunities for transnational activism than do global flows between societies or markets. The evidence analyzed here suggests a refutation of that prevalent antithesis. Instead, it supports the synthesizing hypothesis of this study: The more markets and societies globalize and the more states interact, the more transnational activism occurs. The research conducted here develops on a promising explanatory typology that is the best attempt to answer the main question about activism in international relations (IR) studies at present. This dissertation builds on such theory, moderating short-range and statist imbalances in conventional IR and cross-national (comparative) research on the consequences of interstate regimes and political opportunity structures, respectively. The study goes on to make this prior scholarship more accurate, comprehensive and reflective. First, tests of the prime theory over a longer history, which predates 1945, here elevate

globalism toward a favorable condition that is as consequential as internationalism for activism across borders. Second, this study conceptualizes four explanatory processes--or chains of causal mechanisms--that link activism mainly to encouragement from

globalization. These original models expose a grand, causal theory to have outpaced its necessary processual, mechanismic bases. Finally, the study addresses the spatial transnationality and transnationalization of activism. It extends the typology of explanatory processes to distinguish the primary scale of activist actions from the locus of activist causes, along a domestic-foreign frontier. The extension renders as

unexamined a conventional assumption that activism transnationalizes through a one-dimensional globalization from local toward global proportions. The dissertation uses qualitative, case-study and process-tracing, methods to compare and generalize beyond two transnational activist campaigns. These campaigns are situated temporally from the 1860s to the 1950s, geographically through inclusion of actors based in Brazil, and thematically via incorporation of biodiversity in activist deed

or discourse.