The call for an Inter-Civilizational Dialogue informed by cosmopolitical forms of Comparative Political Theory as a way to address our unprecedented global challenges is among the most laudable projects that students of politics and related fields across the world have put forth in centuries. Unfortunately, however, up until this point the actual and potential contributions of the Indigenous or 'Fourth' World and its civilizational manifestations have been largely ignored. This has clearly been the case in what refers to Indigenous American or Abya-Yalan cultures and civilizations. The purpose of this dissertation is to acknowledge, add to, and further foster the contributions of Indigenous American cultures and civilizations to the emerging fields of Comparative Political Theory and Inter-Civilizational Relations. Guided by a cosmopolitical concern for social and environmental justice, this work adds to the transcontinental and transdisciplinary effort to decolonize knowledges and practices by offering socio-ecologically balanced alternatives beyond the crisis of globalized Western modernity. This work draws on three broad Indigenous traditions, Mesoamerican, Andean, and Native North American, to offer some historical and contemporary examples of the many possible ways in which the recovery, revalorization, and revitalization of Indigenous modes of thought, practice, organization and planning can contribute to foster forms of comparative political theorizing that address the challenges of a global age bedeviled by the confluence of social and environmental crises of an unprecedented scale and scope. The dissertation first introduces comparative political theory as a framework for the inter-civilizational dialogue, arguing that Indigenous contributions have been marginalized and must be considered. Part I then focuses and elaborates on specifically Mesoamerican contributions; Part II is dedicated to Andean contributions; and Part III to Native North American contributions. The dissertation closes with a brief reflection of how Indigenous American contributions can help us address some of our most crucial contemporary global challenges, especially in what concerns the construction of cosmopolitical alternatives built on post-anthropocentric forms of socio-ecological justice.