In That They May Be One, Dawn Nothwehr offers two books in one: an introductory textbook on the Catholic Church’s participation--failures and successes--in the history and current status of racism, tribalism and xenophobia worldwide, and a sourcebook of church documents addressing these problems around the globe. The scope is breathtaking, bringing together histories of ideas and events, church teachings, and social science research. Along the way, Nothwehr argues that the church needs to become more aware of its own complicity in structures of unearned advantages and that liturgy, especially preaching, is the best way for the church to call its members to account.

Part I, "Background on Racism and Discrimination," begins with a sweeping historical overview of the construction of the idea of "race" in Europe and North America, on the one hand, and China and Japan, on the other. This is so much to cover that the discussion seems too brief. Yet Nothwehr succeeds in showing that racism is a global phenomenon that has developed differently around the world.

Chapters 2 and 3 focus on the teachings of the Catholic Church. Chapter 2 describes the ambiguity of church teachings on slavery, colonization, and racism from the Bible to the Fathers, the Middle Ages, and more recent papal teachings. Invaluable for the researcher are charts outlining eight different teachings on slavery, indicating which thinkers or councils have held each position and the documents in which the ideas appear. In contradistinction to this ambiguous legacy, Chapter 3 summarizes the strong and ancient foundation that exists in Catholic doctrine, theology, and ethics for affirming the dignity of every person: Trinity, creation and the image of God, incarnation, and the church. Throughout these first three chapters, Nothwehr turns repeatedly to sociologist Albert Memmi’s definitions of racism to frame the discussion.

Chapter 4 utilizes the social sciences to introduce some theories about how racism, tribalism, and xenophobia arise; and Chapter 5 suggests nine avenues the church should pursue in its ongoing struggle against racism, including attending to its own multicultural character, working to support vulnerable populations such as migrants and women, and exploring the interconnectedness of economic and racial injustices. Nothwehr forthrightly reminds the church of its need to address its own institutional racism: "The Church often stands as an example of white privilege. If it is to be a credible teacher of racial justice, it must openly recognize the reality and the dynamics of white privilege and the dominant gaze" (96).

Part II, "Church Documents on Racial Justice," collects in an extensive annotated bibliography key church documents dealing with racism, tribalism, and xenophobia from the Vatican, Africa, Asia, Europe, Latin America, North America, and Oceania. Teachers will find the introduction, "How to Read a Church Document on Racial Justice and Related Issues," useful in guiding discussion and research on these documents. Aiming to present representative key texts that are accessible to a Western audience, Nothwehr skillfully organizes the material to facilitate classroom study. For each document, she includes the title, author, and date; the location of the full text of the document (often online); an abstract; an historical note; discussion questions inquiring into the circumstances surrounding the text’s publication as well as its contemporary significance; and a brief excerpt, usually several paragraphs. Nothwehr streamlines the material by standardizing the format and omitting most internal references. Because the documents come from various levels of church authority--archbishops, bishops’ conferences, Vatican commissions, popes--Nothwehr describes the collection as "uneven." Nevertheless, the result is a nicely balanced overview of how church leaders have addressed racism, tribalism and xenophobia around the globe.

Nothwehr provides a valuable service in assembling foundational ideas and Catholic social teaching documents on racism. The proliferation of definitions of racism, tribalism, and xenophobia demonstrates the intractability of these phenomena. While the emphasis on the collective church is appropriate in a volume on Catholic social teaching, the work also implicitly illuminates the need to develop concrete, specific ways for ordinary Christians to put these teachings into practice.

That They May Be One is recommended as an overview of the Catholic Church’s global involvement in the problems of racism, tribalism, and xenophobia. The book would serve well for a graduate seminar in which students could research the ideas and primary source materials further. As each chapter in Part I could stand alone, one could easily omit chapters or change the order in which they were read. The first three chapters, packed with ideas, would challenge those without a background in theology or philosophy; also, more theological analysis of why humans, especially Christians, have developed these insidious notions of race when it presumably could have been otherwise would have added an important dimension to this resource. For these reasons, the book is not generally recommended for undergraduate courses, though it would be very helpful in preparing lectures or identifying documents to assign.