It's named after... Josiah Whitney.
From previews, we know one of the Mountains is called Josiah.
So when we've been calling the tallest mountain Chiliad, it makes sense for the tallest mountain in the game to be called Mt. Josiah, and the mountain to be based off the mountains in the Sierra Crest.
Edited by zombie elvis, 06 June 2013 - 12:17 AM.