>What do you mean with usurption by a greater force here? We can say with
>some certainty that the Celtic countries were not converted by foreign
>armies invading them, at least that's what the records say.
Christianity seems to have swept across Europe at a rate of knots, which is what I was meaning by a 'greater force' rather than an actual army beating everyone to death with bibles. How did Christianity so quickly replace their own religions and beliefs?