From Alexander Nazaryan's takedown of Michel Pastoureau's The Bear: History of a Fallen King:
In cave paintings, in fact, "the bear, except for man, is the only living creature that is shown upright," which is what politicians would call a special relationship. The bear is the emblem of Artemis; a she-bear nursed the prince Paris, the same who later fancied Helen. King Arthur, rock star of the Middle Ages, was an "ursine divinity," according to Pastoreau. And for the pagan tribes of Germany, "the bear was much more than the king of the forest … it was the quintessential totemic animal."
And that is precisely the problem. The early Church tended to not practice much tolerance toward pagan rites, subverting those it found attractive (the whole Virgin Mary business) while suppressing those it feared would threaten its stature. The brown bear of the European forest, with its unchecked aggression and appetites, clearly fell into the latter category.
Thus, circa 1100 C.E., the Church launched what Pastoreau regards as a massive smear campaign to wean Germans, Scandinavians, and Europeans off their ursine adoration. This was done by denigrating the bear while promoting theretofore "lesser" animals such as lions; the process was made easier by the fact that while anyone who came into contact with a bear was not likely to emerge with sound life and limb, lions were distant enough that Church scribes could paint them as they wished.