I add :
From what point was Vladimir the Baptist at first a fierce persecutor of Christians, and then suddenly changed sharply?

He chose religion as his wife: that the prince should stand above the pope (and not as in Catholicism, where the pope could exclude the king from the church, and he was conducted to manipulate), and even a little for the beauty of the rites.

UNICEF, another important factor was that Christians are not forbidden to bow.