How does the history of U.S. foreign relations appear differently when viewed through the lens of ideology? This book explores the ideological landscape of international relations from the colonial era to the present. It offers a foundational statement on the intellectual history of U.S. foreign policy. This expansive collection shows the work of a broad diversity of ideas and voices in U.S. foreign relations history, featuring not only presidents and diplomats, but also indigenous peoples, grassroots activists, and even children. This field-expanding book will have an enduring impact on teaching and writing in foreign relations history.