Christian world

Christendom has several meanings. In a contemporary sense it may refer to the worldwide community of Christians, adherents of Christianity; or the collectivity of Christian majority countries, or countries in which Christianity dominates, or nations in which Christianity is the established religion.

In its historical sense, the term usually refers to the medieval and early modern period, during which the Christian world represented a geopolitical power juxtaposed with both the pagan and especially the Muslim world. In the traditional Roman Catholic sense of the word, it refers to the sum total of nations in which the Catholic Church is the established religion of the state, or which have ecclesiastical concordats with the Holy See.

The term cristendom existed in Old English, but it had the sense now taken by Christianity (as is still the case with the cognate Dutch christendom , where it denotes mostly the religion itself, just like the German Christentum). The current sense of the word of "lands where Christianity is the dominant religion" emerges in Late Middle English (by c. 1400). This semantic development happened independently in the languages of late medieval Europe, which leads to the confusing semantics of English Christendom equalling German Christenheit, French chrétienté vs. English Christianity equalling German Christentum, French christianisme. The reason is the increasing fragmentation of Western Christianity at that time both in theological and in political respect. "Christendom" as a geopolitical term is thus meaningful in the context of the Middle Ages, and arguably during the European wars of religion and the Ottoman wars in Europe.

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