need an Irish battle name

[thanmuwa]

Brian Boru. 'nuff said.
T.

One of the best suggestions so far, IMHO.

In the Wikipedia article Táin Bó Cúailnge, Cú Chulainn is written as Cúchulainn. I know Wikipedia isn't the most reliable source, but are both correct, or only the first?

Neither are wrong. It literally means the hound (Cú) of Culann, his real name was Setanta. I am sure Wikipedia will be able to tell you why he had to be Culann's guard dog .

What's the proper pronunciation of Cocidius? Is it just like you'd say it in English?

It is Latin so no-one really knows. Any way you want to?

EDIT (the third):
Leaning towards Brian Boru; this more allows for a Christian persona.

Other suggestions, if you want a Christian linkage, are the various Irish missionaries who brought Christianity back to Europe. Perhaps the one most relevant to this board would be St. Colum Cille, know to the Scots as Columba. Alternatively, St. Brendan the Navigator is linked to the US.