I frequently encounter people who claim to be investigating "Celtic spirituality". By this they typically mean reconstructions of Druidry filtered through romantic legend.
I always give them a litany of the Celtic saints in reply: Christian, orthodox, and a light to the world in a dark time.
I have a personal devotion to St. Aidan and St. Columcille (Columba).
"I frequently encounter people who claim to be investigating "Celtic spirituality". By this they typically mean reconstructions of Druidry filtered through romantic legend."
Indeed there are. I have a cousin who is doing just that, though she's a bit of a loon! There are also "Celtic Orthodox" groups who claim to be Orthodox, but they are only a bit less loony than the Druid inspired crew!
It is good that you mentioned light in a dark world. That has always been my image of Iona and Lindisfarne and these two great saint/monks who approached God there.