In Japanese, some names exist in both people and prefectures or cities. For example, Fukushima Industries Corporation is not named after the prefecture of Fukushima (福島県) or the city, but after Nobuo Fukushima (福島 裕).
Which comes first? Is it that there's the name of a city or prefecture, and people who live there get their name from it, or was the city or prefecture named after someone famous? Or both?