Just like you visit maps.google.com.tw or maps.google.co.kr or maps.google.co.jp, you can see their own language shown on every country. I
For the V2 Maps API:
You can add an optional hl parameter to the tag when including the Google Maps API, specifying the domain language to use, as in the following example:
Localization of the Google Maps API
Screenshot:

You may also want to check out the following resources for further reading: