The drive to protect, purge, and purify radically reshaped European society over the course of the early modern period. We can see its effects in politics, the economy, migration, law, and social life, as well as in religious institutions, rituals, and thought. It is striking that definitions become sharper and differences between religious communities more bitter over this period. The number of religious exiles and refugees grows throughout the seventeenth century, and purgative spasms recur in the eighteenth century when we might think that Europe had put all of that behind it as religious faith supposedly began to wane. Instead, Louis XV launched a crusade against Huguenots in the Cevennes Mountains in 1702, the archbishop of Salzburg forced 20,000 Lutherans into exile in Prussia in 1732, and the British loaded more than 11,000 Catholic Acadians onto boats and shipped them overseas in the later 1750s. Religious purgation was alive and well in the Age of Reason.

In order to understand why, we need to look more closely at how the innovations and actions of the fifteenth and sixteenth centuries became the norms and customs of the seventeenth. For that we need to look at how Christians of all confessions, and Jews and Muslims too, began rethinking and reforming the tools, personnel, spaces, and creative life of their religious communities. Refugees and exiles were frequently the most committed and best connected members of their religious communities. They were authors, artists, lawyers, teachers, and bureaucrats, and they worked directly and indirectly for change using the most advanced means available. New forms of technology, particularly printing, allowed texts and images to be used more creatively. New schools, curriculum, and pedagogy coming out of the humanist movement fed a drive to improve the training and raise the professional standards for clergy. New ideas about how communities should relate to God or conduct ritual life changed the spaces, furnishings, and liturgies of worship. The experience of purgation, exile, or forced migration led all communities to look again at their own traditions, at the heroes who populated their collective imagination, and at how they communicated their story to their own children. What is perhaps most telling here is that Jewish and Muslim communities picked up on many of the same changes to tools, personnel, spaces, and creative life, and used them to firm up their own traditions and identities.

The social body had a mind, but was never of one mind. Its many members had varying physical needs, and no single way of meeting them. Thus far we have seen how tensions of the late medieval period began to complicate Europeans' understandings of what it meant to be a Corpus Christianum, or Body of Christ. In this chapter, we will see how ways of thinking and ways of acting began to diverge in that Body, and tear it apart. We have already seen how anxieties about external and internal threats gripped Europeans from the fifteenth century, and how they responded with strategies to separate, contain, prosecute, and purge these threats. The result was a flood of religious exiles and refugees that poured out of particular nations and cities and washed around Europe and across the globe from the fourteenth through the eighteenth centuries. It was because of these late medieval and Renaissance-era tensions that the religious refugee and exile emerged as mass phenomena in the early modern period. We have also looked at the paths that some individuals took in their thinking and with their feet when they were separated, prosecuted, or purged. Their mental and physical migrations took them across Europe, the Mediterranean, and the Atlantic, and transformed the places where they settled. The migrations of religious refugees and exiles fundamentally shaped early modern political, economic, and cultural life.

Religious doctrines lay at the heart of both the threats and the strategies, and thus far we have sketched only some of the main differences between Jews, Christians, and Muslims, and between Catholics, Lutherans, Radicals, Calvinists, and others within Christendom. A thorough comparative discussion of the theologies of the Reformation is beyond the scope of this book. Yet it is helpful to look briefly at a few of the doctrines that were most contentious and were most often used to mark and divide. We will then see how religious communities worked to put their beliefs into action through different forms of charity. Many religious refugees and migrants needed it, and many religious communities thought that help to the poor and needy was the best measure of true faith.

Religiously driven exile may have emerged as a mass phenomenon in the early modern period, but how did individuals experience it? What was it like to look at the world from the position of the religious refugee? By comparing the experiences of a range of individuals from across different faiths, we can begin to put a human face on what was often an inhuman tragedy. Some weathered this better than others, and all were deeply marked by it. In many cases, removal was not a one-time thing. Some moved frequently in search of a place that would allow them to build a community. Others found that community and turned it into a test case for ideas and an incubator for missionary activity. Some were in constant motion physically because they were in constant motion intellectually, moving from one creed to another in search of something that reflected their deepest convictions. Women often had less freedom to move, and so it is important to consider the experience of those who did not manage to escape, particularly since their followers later wrote powerful accounts turning them into martyrs for the cause.

Refugees and exiles needed shelter, and after having considered some of those who fled, we will look at a range of the places that they travelled to. Some of these places were relatively open, but others quite closed. In most cases their own recent history shaped the way these cities or territories responded to the waves of exiles and refugees who appeared at their gates. Cities with a history of accepting strangers continued absorbing these new groups, though usually with some effort to control where and how they would live. Other cities and territories became shelters for a particular group, and slowly turned into fortresses of that group's orthodoxy – their own exile past did not prevent them from expelling others in turn. Some refugee cities adopted rules without rigorously enforcing them, and so developed gradually into open, international, and often quite prosperous centers.

Both the refugees and their refuges were fundamentally changed by the dynamics of religiously driven exile. It was the key factor shaping the ideas of some of the most influential thinkers of the early modern period, and it would also direct the political and economic development of cities around the Mediterranean, in continental Europe, and in America.

In order to understand how exile and expulsion could become mass phenomena from the late fifteenth century, we need to look at how European Christians of the centuries before this pictured their society and their relation to God. There was little unity and certainly no uniformity of views, and broad gaps between ideal and reality were the norm. When many Christians described community, they used the metaphor of a human body and in particular the Body of Christ. The metaphor of the Body had different linked dimensions: the social Body of Christians (Corpus Christianum) drew ultimately on the spiritual Body of Christ (Corpus Christi). This physical metaphor for the social community of believers distinguished Christianity from Judaism and Islam, and provided a very powerful imaginative framework for thinking about what characterized a pure social community and what threatened it.

Pictures and rituals put the idea of a Corpus Christianum at the centre of the Christian imaginary, and European Christians took responsibility for failing to reach the ideal community that it represented. But throughout the fourteenth century they became increasingly aware of other threats to that Body. There were threats from outside: the Ottoman Turks represented the biggest external threat, and the rising tide of Islam seemed repeatedly to be on the verge of drowning the Corpus Christianum entirely. And there were threats from within: heretics who rejected Catholic doctrines and structures, witches in league with the devil, and Jews who stubbornly refused to accept Christianity were all infections in one or another part of the body. Left unchecked, these infections would spread like a contagion across the whole Body of Christ. Religious leaders and institutions ought to be the spiritual doctors who could halt this contagion, but they often seemed too divided and preoccupied with their own interests to do much good. A Body thus weakened needed strong purgative medicines to restore it to health: doctors cut into the veins of sick patients to release bad and infected blood, gave emetics to trigger violent vomiting, enemas to empty the bowels, and diuretics to clear the bladder. The source of sickness had to be eliminated from the body before healing could begin.