“The Middle Ages” often evokes images of priests and crosses. The dominance of Catholic, and to some degree Orthodox, Christianity tends to form the popular conception of what it was to, erm, get medieval, and also leads to questionable beliefs about the period. Namely, we have the idea that the dominance of Christianity made the Middle Ages a time of ignorance, which is one of those arguments that doesn’t bear much scrutiny because a) the institutions of the Church actually helped preserve Classical learning by keeping writing alive and well, and b) much of the Middle Ages was defined by a complex relationship between paganism and Christianity. In rural areas in the “central” part of what would become Christendom (and, later, the cultural conglomerate known as Europe), pagan practices survived long after conversion during the early Middle Ages. However, I’m focusing on the more obvious case of just how long it took for Christianity to really grab hold in northern and Eastern Europe.
The Grand Duchy of Lithuania, the largest state in Europe during its prime, remained officially pagan until 1386 when it joined crowns with the Kingdom of Poland. That alone is fairly telling.
More telling, perhaps, were the various crusades carried about in the Baltic, roughly stretching from the late twelfth century onwards. The tribes along the Baltic coast were, by and large, of polytheistic faith even after the Vikings had decided to cast in their lot with the Christians. Missionaries to the Baltic lands did have some small success obtaining conversions, but would generally suffer attacks from neighbouring tribes afterwards, leading to dead priests, burned churches, and tortured converts. Christians began as a persecuted group in this region, and the Sword Brothers were formed to defend Christian settlements from incursions by hostile raiders. More aggressive actions by the Teutonic Knights, who gave themselves license to carry out continuous crusades, led to the expansion of the Ordenstaat, a unique polity ruled by a religious order. However, the Teutonic Knights came under criticism for, while their efforts at conquest and settlement were all well and good, their record for actual conversions was abysmal. While marching on Reisen (raids, but more formal and noble and all that) with knights from all over Western Europe twice a year led to plenty of forced conversions in the countryside, the people didn’t hold their new faith all that well and the Knights had to go out and do it all over again, with similar results. Mind you, this is exactly what the Saxons experienced during the Wendish Crusade in 1147, which made their efforts feel rather pointless. And while the popular view of Teutonic Knights seems to lean towards ruthless German conquerors, Duke Konrad of Mazovia initially invited them into Prussia in 1226 to defend his own lands after his unsuccessful incursions in the region.* Which is to say, this bit of Europe was far from Christian throughout most of the Middle Ages.
More clearly: I’ve read some books and articles that treat the Teutonic Knights’ Reisen as some sort of tourist industry, where knights from England or France or Germany would come over when there was no official crusading in the Holy Land to be done, or because it was just closer and easier, to go bash some pagan heads and talk chivalry a while. Why anyone would view the genuine difficulties faced on the Reisen as fun is beyond me; the raids aimed at the Grand Duchy of Lithuania took place in a swampy region, only really traversable if the ground was frozen or dry enough. Death and disease were common, the locals were hostile, and the whole affair was rather unpleasant. It was a serious conflict, and those partaking in it took it seriously as well.
In any case, after 1386 the Teutonic Knights weren’t about ready to pick up and leave now that Lithuania was Christian and all, and instead painted Jagiello’s baptism as a “false” conversion, with most of the countryside still practicing paganism. They were, for the most part, correct, since they didn’t need look much further than their own Baltic peasants to see how well Christianity took hold in these parts, but the point was made moot by their defeat at the hands of Poland-Lithuania at the battle of Grunwald in 1410. Pagan practices continued in the Grand Duchy of Lithuania well into the fifteenth century.
It is a shame that after so long holding on to pagan beliefs, there are few written records of Baltic and Lithuanian religion beyond a mentions in Crusader Chronicles from the region, mostly because Christian chroniclers didn’t have much interest in recording, and possibly spreading, them. But, as Robert Bartlett theorized in his book The Making of Europe: Conquest, Colonization and Cultural Change 950-1350, the medieval European identity as a shared cultural entity, first forged by the idea of Christendom and Crusading, emerged thanks to Christian interactions with Paganism among the Scandinavians, Saxons, and Baltic peoples, and with Islam–a nearly constant feature of the Middle Ages. Medieval identity partly set around ideas of Christendom and Heathendom. To pick out one example, the mention of the knight riding “in Christendom as in hethenesse” in The Canterbury Tales (and I might note “in Pruce/ In Lettow he reysed and in Ruce”) shows the idea was well enough known. While a very real undercurrent of paganism ran in “Europe proper”, it was on the borders that we found overt examples of conflict between paganism and Christianity. Some areas of Europe were truly Godless, and no small part of Medieval life emerged from the pagan element clashing and mingling with the Christian one.
*For a great discussion of the idea of victims and aggressors during the Baltic crusades, try William L. Urban’s article “Victims of the Baltic Crusade” (1998).