I just cannot say less about that. Cultures, that were Celtic, then Catholic, and now are slowly getting atheist. Why are conservative movements trying to make them Catholic, not Celtic?

They talk about that Pagan Celtic virtues, and call that "Christian virtues". They say Celts practiced human sacrifices. But Christians did that on even larger scale. Apart from burning people on stakes, they believed, and still believe, in ritual cannibalism. Catholics do believe that the communicant actually turns into human meat, not just symbolizes it.

On the other hand, Pagan societies were generally more tolerant than modern Christians. This may be affected by the fact, that in early middle-ages, only the most-educated people had actual contact with the outside world. So, all views on different cultures, were basically in the hands of merchants. Villagers knew that "Persians are awesome and make flying carpets", because someone tried to sell that flying carpets. They didn't know that the carpets don't fly, because nobody could even think of affording them. On the other hand, they knew that Huns are evil, because the Huns raided their village several times - but that was the result of violence.

In early middle-ages, people weren't against "different things" by default. They could oppose the culture of someone that attacked them, robbed them, raped them. Today, let's say you are a black American, and are walking around some small village, asking for directions. You didn't harm anyone, yet people will be against you. Notable fact, medieval Christians also didn't like foreign cultures, and were against discovering new things.

In middle-ages, you would often struggle upon a Christian culture that doesn't accept Pagans - but it was rare to struggle a Pagan culture that doesn't tolerate Christians. Christians just were more... elitist. They had their Latin, they said "we can read". Pagans had their runes, could read them, but still, "they cannot read".

PLUS, Pagan societies were more friendly towards the environment. While Christians talk of "martyrs" who attacked a sacred grove and got killed. Following the same way of thinking, I'd speak of Hitler as a saint for Germany, because he lost everything, trying to expand his Germany, and not just his life.