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Christianization is a term used to indicate the process of making something “Christian.” When a nation’s population turns to Christianity as its official or predominate religion, then that nation has been Christianized, especially if it is under a Christian ruler. The idea of Christianizing a country or nation is not found in the Bible. The Bible’s focus is on evangelization—sharing the gospel—but not political or military Christianization campaigns, which have historically included forced baptisms and coerced recitations of creeds. Christianization can also refer to the act of coopting a pagan practice, building, or holiday and using it for Christian purposes. It’s possible that some pagan rituals were Christianized for use in modern celebrations of Christmas, for example.
One of the earliest examples of Christianization on a national level occurred under Emperor Constantine. It is doubtful that Constantine was a Christian during the main part of his life, although he may have been saved in his old age (dc Talk and Voice of the Martyrs, Jesus Freaks: Volume II, Bethany House, 2002, p. 230). Constantine did end the persecution that Christians had suffered under the previous Roman emperors, and he favored Christianity, but he also allowed pagan religious practices to continue. Although Constantine did not specifically seek to make his empire “Christian,” he is viewed as one of the first emperors who allowed Christianity in the Roman Empire and encouraged its growth.
Later, there were other rulers such as the Frankish King Clovis I and Prince Vladimir of Kievan Rus who sought to Christianize their entire kingdoms. Unlike Constantine, who tolerated paganism, these rulers did not, as they wanted to promote political unity. Richard Fletcher, history professor at the University of York, states in an interview in Christian History, “It isn’t until the Frankish kingdom of Charlemagne in the eighth century that we see force used to coerce conversions, specifically in the campaign against the Saxons” (“Interview—Converting by the Sword,” Issue 63, 1999). Mass baptisms were typically held to Christianize the subjects of Roman Catholic kings and rulers in the medieval period.
Obviously, forced Christianization is unbiblical, as people cannot be forced to place faith in Jesus. Salvation is a gift from God because of His grace, and individuals must accept this gift freely and voluntarily (Ephesians 2:8–9). Those who underwent forced conversions may have confessed that they were Christians, but that does not mean they believed in Christ. Scripture emphasizes the importance of the heart’s belief matching the mouth’s words: “If you declare with your mouth, ‘Jesus is Lord,’ and believe in your heart that God raised him from the dead, you will be saved” (Romans 10:9).
To aid national Christianization, many rulers incorporated syncretism to appeal to the native pagan traditions. Pagan subjects who “converted” to Christianity would often simply add Jesus to the list of gods they already worshipped. Although the continual presence of Christianity did eventually influence many to truly place faith in Jesus, the quick and forceful conversion of pagans was not initially successful at reaching them for Christ (Fletcher, op. cit.). A person cannot serve the one true God and also worship false gods at the same time, for this is clearly condemned in Scripture (Exodus 20:3; Matthew 6:24).
Probably the most controversial aspect of Christianization was the threat of violence if one did not submit to “conversion.” Many European explorers such as Christopher Columbus saw that to extend a nation’s borders “was to extend Christianity; to conquer and enslave new lands was to spread the gospel” (Kevin Miller, “Why Did Columbus Sail?” Christian History, Issue 35, 1992). Conquistadors would invade a land, capture whole peoples, and then force Christianization upon the natives: “Survivors were offered few options but to submit to the sacrament of baptism and become Christians. Latin America—by far the most Christianized region of the entire world—has remained very Catholic ever since” (Dyron Daughrity. Roots: Uncovering Why We Do What We Do in Church, Chapter 2, ACU Press, 2016).
Although non-forceful Christianization could be said to have had some good in it, in making the gospel readily available and providing a Christian presence, it is not altogether positive. There is always the danger of changing behavior to conform to a cultural shift without changing the heart. As stated in Jesus Freaks: Volume II, “As Christianity went from being persecuted to being fashionable, a trend was begun that still poses a challenge to believers today: cultural Christianity” (p. 230).