・ In china they show taiwan as a region of china
It has something to do with the local laws that enforce the representation of the country's map, as explained with the india/china example india may juridically attack google for not showing the wanted region as theirs ; also big market for google.
・ Sometimes they follow the UN convention sometimes not.
The most interesting is the conclusion, the presenter J-C.Victor says *"Google is an agnostic cartographer, pretending that there's no unique map […] but users will see the map their country wants to see" *
http://www.arte.tv/guide/fr/060139-021-A/le-dessous-des-cartes (It's in french, there's probably german subtitles)