So is the official name Valentia now. Am I imagining that it used to be Valencia? That hard T at the end of the word just seems wrong for some reason. The soft S sounds makes the word sound refreshing. Believe me, make a "tuh" sound, then make a "sah" sound. You'll feel much better with the latter.
It seems both are names of real places, so Fire Emblem's penchant for using real world place names isn't a big help, there.