This book is an original study of Cold Rush, an accelerated race for the extraction and protection of Arctic natural resources. The Northernmost reach of the planet is caught up in the double developments of two unfinished forces rapidly progressing climate change and global economic investment - working simultaneously in tension and synergy. Neither process is linear or complete, but both are contradictory and open-ended. This book traces the multiplicity of Cold Rush in the Finnish Arctic, a high-stakes ecological, economic, and political hotspot. It is a heterogeneous space, understood as indigenous land within local indigenous Smi people politics, the last frontier from a colonial perspective, and a periphery under the modernist nation-state regime. It is now transforming into an economic hub under global capitalism, intensifying climate change and unforeseen geo-political changes. Based on six years of ethnography, the book shows how people struggle, strategize, and profit from this ongoing, complex, and multidirectional change. The author offers a new theoretical approach called critical assemblage analysis, which provides an alternative way of exploring the dynamics between language and society by examining the interaction between material, discursive, and affective dimensions of Cold Rush. The approach builds on previous work at the intersection of critical discourse analysis, critical sociolinguistics, nexus analysis and ethnography, but expands toward works by philosophers Michel Foucault, Gilles Deleuze, and Felix Guattari. This book will be of interest to researchers on language, discourse, and sociolinguistics interested in engaging with social critique embedded in global capitalism and accelerating climate change; as well as researchers in the social and human sciences and natural sciences, who are increasingly aware of the fact that the theoretical and analytical move beyond the traditional dichotomies like language/society, nature/human and micro/macro is central to understanding todays complex, intertwined social, political, economic and ecological processes.