Every word in a Latin sentence contains its complement ("urb" is the origin word. "s" is the ending that means "subject", urb-is where "is" means the complement "of the (urbs)", urb-i where "i" means the complement "to the (urbs)" and so on...) I don't want to complain and it's fine you mix up everything, you do not study Latin...
Ian, I'm italian and I'm actually studying Latin and Ancient Greek, so when you search on the internet "Urbs" and you find "Urbs, urbis, urbi, urbem, urbs, urbe..." you have just ?found? the "declination" of that word. the Declination is the list of letters you have to put at the end of the latin words to give them a meaning in a sentence... (I made a save for these ID:2150589)
both urbs and urbis mean city, i don't know where you got that idea from.
May I complain something? In latin the Title means "new of the city", the actual traduction for "new city" is "nova urbs"
Carry on, that's cool! +1