I'm thinking its Greece for the following reasons. Travel time between Russia and the tower takes a while, but you do go to orbit first. The cut scene of traveling through a storm in the first or second mission could be anywhere. Due to the high storm activity and crosswinds, it reminds me of traveling through a a storm over a large body of water, like the Mediterranean. Armor pieces are strongly influenced by Greek and Roman times, and can be clearly shown in the Titan class items. Here's the big clue, Latin words on the Map and that on the city floor shows the culture of the region. Now I may be wrong, but the first place that popped in my mind is Vatican City. Doesn't necessarily mean it's exactly the Vatican, but rather the general region. Edit: I shouldn't read and post right after I wake up, my grammar is nonsense.