These volumes present over one-hundred primary source and historical documents including book excerpts, court opinions, debates, and interview letters, to name a few. Each document provides insights into the significance of events surrounding conservativism in the United States, from the publication Andrew Carnegie’s “Gospel of Wealth” in 1889 to Donald Trump’s implementation of the Department of Government Efficiency (DOGE) in 2025. Conservatism has played a major role in U.S. politics since at least the Reagan era, and going back to the Nixon administration and before. Conservatism is a political and social ideology that emphasizes the importance of tradition, established institutions, and gradual change. Central aspects of conservatism include the value of national customs and institutions, a cautious approach toward immigration, the importance of authority and order, and a sense of loyalty to the nation and its founding principles. In recent decades conservatives, generally aligned with the Republican Party, have promoted limited government, military might, financial deregulation, and private enterprise as the way forward for the United States. Successful election results in recent years have seen the rise Christian nationalist politics and the emergence of Donald J. Trump as the new herald of a hardline conservativism, one, even, that challenges existing institutions. Yet conservative politics have continuously been challenged by liberal voices in the American polity, including mass movements against authoritarian conservative tendencies and wars of choice rather than necessity. Anti-egalitarian precepts held by Republican conservatives and harsh restrictions against immigrants have, likewise, been lamented by liberal, mostly Democratic opponents. Covering key moments and ideas from previous eras to today, this work explores this all-important thread in American political culture and how it has impacted the workings of government, the economy, national defense, international relations, law and society, domestic programs, and cultural values throughout U.S. history. The documents contained within these sections provide an overview of the history and significance of conservatism in American society, exploring important moments in the ideology’s development from the founding of the country to current times. These volumes present over one-hundred primary source and historical documents including book excerpts, court opinions, debates, and interview letters, to name a few. Each document provides insights into the significance of events surrounding conservativism in the United States, from the publication Andrew Carnegie’s “Gospel of Wealth” in 1889 to Donald Trump’s implementation of the Department of Government Efficiency (DOGE) in 2025.  The material is organized into four sections, each beginning with a brief introduction that examines the importance of the topic through a variety of historical documents. Traditional Conservatism and Anticommunism “Movement” Conservatism and Pragmatism Conservatism and Neoconservatism Hardline Conservatism and Trumpism The documents contained within these sections provide an overview of the history and significance of various forms of conservativism that have been present in the United States since its founding. Each Historical Document is supported by a critical essay, written by historians, teachers, and researchers, that includes a Summary Overview, Defining Moment, About the Author, Document Analysis, and Essential Themes. An important feature of each essay is a close reading of the primary source that develops broader themes, such as the author’s rhetorical purpose, social or class position, point of view, and other relevant issues. Each essay also includes a section entitled Bibliography and Additional Reading that provides suggestions for further readings and research. Appendixes in this book include: Chronological List, which arranges all documents by date. Web Resources, an annotated list of websites that offer valuable supplemental resources. Bibliography lists of helpful articles and books for further study.