Conversion or death

Forced conversion is adoption of a different religion or irreligion under duress. Some who have been forced to convert may continue, covertly, with the beliefs and practices originally held, while outwardly behaving as converts. Crypto-Jews, crypto-Christians, crypto-Muslims and crypto-Pagans are historical examples of the latter.

In general, anthropologists have shown that the relationship between religion and politics is complex, especially when viewed over the expanse of human history. While religious leaders and the state generally have different aims, both are concerned with power and order; both use reason and emotion to motivate behavior. Throughout history, leaders of religious and political institutions have cooperated, opposed one another, or attempted to co-opt each other, for purposes both noble and base, and have implemented programs with a wide range of driving values, from compassion aimed at alleviating current suffering to brutal change aimed at achieving longer-term goals, for the benefit of groups ranging from small cliques to all of humanity. The relationship is far from simple. But religion has often been used coercively, and has used coercion.

Christianity was a minority religion during much of early Roman history, and the early Christians were persecuted during that time. When Constantine I converted to Christianity, it became the dominant religion in the Roman Empire. Already under the reign of Constantine I, Christian heretics had been persecuted; beginning in the late 4th century, the ancient pagan religions were also actively suppressed. In the view of many historians, the Constantinian shift turned Christianity from a persecuted religion into one capable of persecution and sometimes eager to persecute. There are a number of examples of forced conversion throughout the history of Christianity: during the Roman Empire, in the Middle Ages, inquisitions in Spain and Goa, and campaigns by Russian rulers.

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Wikipedia