Not quite sure why Ptarmigan thinks Willy is an English name.

It is very commonly found all over Ireland and Scotland, either as Willy, Willie or William. I don't know enough about Wales!

I think that he is confused because because there was a certain German chap of that name who is probabaly not too popular in parts of Ireland himself, but that fact doesn't make the name unpopular.

And he tends to be called Billy anyway!

Or maybe the Villan's first thought is correct.