Interesting post about Herne, Aslan, lions and Christ over at Quaker Pagan Reflections, which moved me to comment as follows - but I've been thinking about this for a while.
I personally think it's a mistake to conflate the cosmic Christ with the man Jesus. Jesus was sometimes inhabited by the "Christ" (as at the Transfiguration, for example) and sometimes he was just a man (as when he turned away the Samaritan woman at the well, for example).
The concept of mashiach / Messiah (or Anointed One) in Judaism does not apply only to one person, but to being a Chosen One and to the act of sacrificial giving, and according to the Hasidim, there's a messiah in every generation. It's worth reading The Anointed One by Z'ev ben Shimon Halevi and The Seventh Gate by Richard Zimler for two extended meditations on this concept.
I also think that when Paul started building up the concept of Christ, he drew upon the imagery of Adam Kadmon, the cosmic man (or the Gnostic equivalent).
The people of Brittany (around the forest of Broceliande) associated Cernunnos with Christ. There's even a church in Trehorenteuc with a big mosaic deer representing this. There's also a rather interesting icon by Fr Robert Lentz of Christ as Cernunnos (and some thoughtful reflections on it); when I first saw this I was slightly offended on behalf of Cernunnos, but I got over it when I thought about what it meant.
Aslan represents the Christ-archetype, but not the man Jesus. Jesus represents the Christ-archetype, but not the figure of Aslan. Al-Hallaj (and possibly Cernunnos and Herne) represent the Christ archetype, but not Jesus or Aslan. And so on.