Kampong is a name. in fact it's in Thai. "Kam" in this case means gold while "Pong" has many meanings. The one that related to the name is abundant, swell, big. The majority of their people are Tai ethnics. It's just coincident that the name is close to some words. Not to talk that the countries you mentioned are all far away from this village. If there are the same group, why there are no clue of them in other provinces of TH from the south (since all the countries you mentioned are there) to this village?
