DescriptionWhat is the role of perceived environmental factors in settlement, development of civilization, and intercultural interactions? This study seeks to determine how climate, natural resources, and other environmental criteria as historical people understood it from the early 17th century to the mid 19th century influenced the unfolding of events in what we now call the American Southwest. It is anachronistic to say that mankind and technology has overcome environmental influences, and conversely it is deterministic to ascribe too much influence of the physical environment on human history. However, the science of the times coupled with social and cultural backgrounds created systems of discourse as to how the environment operated and influenced the individual and society. These beliefs in and of themselves are vital to better understanding the history in question. Delving into personal narratives, diaries, and other contemporary documents, this study draws out the voices of the people and their intellectual systems to lay out a framework of environmental interpretations and their influences on way of life. Spaniards and Anglo-Americans had unique and occasionally overlapping ideas regarding these dynamics. Often times, people were not aware of the role of such abstract conceptual influences in their lives. On other occasions, however, some actors seem to consciously appropriate environmental discourses for personal, societal, political, or even military objectives. In this sense, not just the environment itself but the network of notions as to how people thought it worked and affected them was pivotal with regard to the wide range of events and relationships that occurred in this place and time, including Spanish expansion and later American takeover. Exploring the way people of different backgrounds perceived their environments and their relationship to it, and how this influenced their lives and relationships with others, can help us better understand our history, and our modernity.