I. INTRODUCTION: THE POLITICAL SCIENCE OF CHURCH AND STATE
Many academic disciplines, including history, law, sociology, and religious studies, bear on the relationship between society and religion, or more narrowly between the state and faith communities. We approach this question with the tools of political science. This paper examines the evolution of religion-state relations in the United Kingdom. We start with political scientists' general statements: "Politics [is about] who gets what, when, [and] how,nl and, "The state . . . successfully claims the monopoly on the legitimate use of physical force within a given territory.''''2 As religion may challenge any state monopoly on the legitimate use of physical force, all societies and states where there is religion must address this potential conflict.
Religions make incompatible truth claims which may involve claims over civil power. When a state contains groups of people of different religions, those groups may make incompatible truth claims, not merely against the state, but against one another. This is a near-universal feature of the modern state. Incompatible truth claims created very difficult problems in early-modern Europe, and were reconciled in different ways - many of them bloody, many of them involving mass forced migration.3 In emerging liberal democracies, however, the state learned gradually to accommodate religions, beginning with the unthreatening ones. It often took time, sometimes centuries, for states to recognize which religions posed no threats to them, and for religions to cease threatening states. The next sections of the paper trace the evolution of this accommodation in one liberal democracy: the United Kingdom. The accommodation began when the U.K. was neither liberal, nor a democracy - in fact, it began when it comprised two separate states.
We will argue that the U.K. is secular, but not (as three prominent religious leaders have alleged) secularwf. This complaint confuses secularity (where the U.K. is coming into alignment with the United States) with secularism (as in, e.g., France and Turkey). We follow Professor Scharffs in defining secularity as the noun corresponding to the adjective secular, and secularism as the noun corresponding to the adjective secularist* "Secularism/ist" denotes ideology; "secular/secularity" denotes ideological neutrality. A secular ¿it state actively tries to keep religion out of the public arena. A secular state is neutral between religions, and between religion and non-religion.
The structure of this Article is as follows. We first set out relevant facts about the two religious settlements in the treaty-state of Great Britain, with particular attention to the accommodations that had been reached by the time of the American Revolution between English and Scottish conceptions of religious toleration, and between the state and the most recalcitrant religious groups. We then turn to American politics in the Founding era in order to illuminate the British (especially Scottish) antecedents of the Establishment and Free Exercise clauses of the First Amendment. In the final section we return to the United Kingdom and chart the gradual spread of the "First Amendment" principle of secularity there since the 19th century.
II. THE REFORMATION IN THE U.K.
Protestant Christianity was established in (what is now) the United Kingdom by two routes. They were very different. In England, Wales, and Ireland the dominant form was Erastian.5 In Scotland, it was Calvinist/Reformed.6
The well-known origins of King Henry VIII's quarrel with the Roman Catholic Church were geopolitical. His first, Spanish wife had failed to produce a male heir.7 There was a risk that England might therefore fall into the territories of her nephew Charles V, head of the Hapsburg dynasty. Henry's own claim to the throne was shaky, dependent on his father's victory in battle in 1485.8 Pope Clement VII refused to annul Henry's marriage, so in the Act of Supremacy (1534) Henry declared himself Supreme Head of the Church of England. …