[Steve_Seattle]

There was an excellent article on this topic in the now-defunct "Gnosis Magazine." The magazine still has a web site (keywords "Gnosis Magazine") from which - I believe - back issues can still be ordered. The issue in question is #45, "Esoteric Christianity." The article was titled, "Looking for Celtic Christianity."

[Publius]

When "Gnosis" went out of business, I was saddened. It was one of the best magazines I had ever encountered.