In light of recent explorations into the interface between human agency and the agentic qualities of matter, the article revisits Michele Serres’ notion of a natural contract to explore the relationships between materiality, environmental politics and citizenship. In a break from conventional renderings of environmental citizenship, the article argues that nature enters into politics alongside human subjects, through insurgent socio-ecological assemblages. In a case study of the 2008 Ecuadorian constitution, with its organizing principle of buen vivir and provisions enshrining the rights of nature, the idea of a natural contract proves a useful heuristic device for probing the political intertwining of human and nonhuman. At the same time, it falls short in characterizing the dynamic socionatural insurgencies that transgress dominant orders and perform alternate modes of being, ultimately leading to such things as formal constitutional change. Moreover, the secular contractual language of the Ecuadorian constitution tends to efface the spiritual content of the indigenous cosmovisions that significantly inform its principles. In light of this, the second part of the analysis probes the way human actors attach meaning to their involvement in socionatural insurgence, with an emphasis on the sacred as an important and often overlooked dimension of political-ecological struggle. Taking the Latin American movement for water justice as its empirical referent, the article locates the spiritual dimension as a vital ontological and discursive bridge facilitating human actors’ embodied engagements with their ecological surroundings. In this way the sacred makes key contributions to assembling human and more-than-human elements within the insurgent ecologies of citizenship.