The First Amendment to the U.S. Constitution provides that “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof.” Since the Supreme Court first applied the Establishment Clause to the states, the court has maintained that the “background and environment” that produced the Religion Clauses is essential to understanding their reach (Everson v. Board of Education, 330 U.S. 1, 8 [1947]). It is unsurprising, therefore, that a “Companion to the First Amendment and Religious Liberty” would deal heavily in constitutional history. Yet anyone familiar with the origin of the First Amendment would know that a history of American religious liberty would also delve deeply into church history. This particular volume, however, does one better. The contributions to this volume—all of them by top-flight scholars—almost uniformly reflect the concerns of religious Americans. The volume is, therefore, unusually useful as a coherent view of the pro-religious side of disputes about religious liberty today. It also serves as a kind of contemporary artifact of the history of the church in America: this is how the church, broadly speaking, conceived of religious liberty in 2020. What is missing, of course, are the non- or even anti-religious views that are increasingly influential in American society.

The volume is divided neatly between three parts: “Philosophical Foundations,” “Historical Interpretations,” and “Law, Politics, and Economics.” The philosophical portion has little to do with history, though it includes several intriguing analytical arguments in favor of religious liberty.

The history portion marches from the colonial era to contemporary Supreme Court doctrine, largely with a historian's eye for the details within the big picture. Most of these essays cover well-trod ground (many of them relying heavily on the authors’ own prior work) but they are well-wrought, reliable summaries. The essay by Michael D. Breidenbach does a bit more: it innovatively places the American rejection of the medieval doctrine of ius patronus front and center of the history of disestablishment: from the Continental Congress forward, American officials declined to exercise the right of civil authorities to name the Catholic bishop within their territorial jurisdiction. His account shows original research, including the fascinating detail that then-Secretary of State James Madison, after officially declining to name a bishop for the newly held Territory of Orleans, privately expressed his preference that John Carroll, already well-known to Madison and President Jefferson, would take the position. (Though Carroll did not become bishop, he did administer the diocese for another decade.)

The essay by Zoë Robinson canvassing the history of the Supreme Court's foray into religious liberty provides a nice, if necessarily selective, overview. Her task was profoundly unenviable: making sense of the court's decisions of the past seventy years is like putting an egg back in the shell. A reader interested in getting another take on the most recent cases involving “institutional” liberty would be well served to read the essay in the same volume by Steven D. Smith.

Given the centrality of history to the Supreme Court's approach to the Establishment Clause especially, it is unsurprising that the essays dedicated to “Law, Politics, and Economics” include snippets of history. The piece by Vincent Phillip Muñoz, in particular, is an important contribution to the intellectual history of natural rights. He argues that the natural right to liberty of conscience was both deep and narrow. With respect to laws targeting worship (which he admits was woefully underdefined in the historical materials), the right was deeper than it is now: the government simply had no jurisdiction to interfere with religious worship whatsoever. With respect to general laws that regulated morality, however, there simply was no natural right at all. Muñoz's account may be correct, but nevertheless insufficient to settle disputes in a society, like ours, that is far more religiously and morally pluralistic than the founders’.

Overall, the essays in this part both analyze how lawyers and political theorists use history to gain leverage in constitutional disputes, and, in some cases, illustrate how they do so. Altogether they provide cutting-edge reflections from some of the smartest American scholars on the pro-religious-liberty side of an ongoing, and increasingly heated, debate.