As far as I know, every country has many local communities with their own dialects. For instance, Hindi, Telugu, etc. in India, Dzonkha, Charshokpa in Bhutan, Amharic, Tigrinyaa etc. in Ethiopia, and Hausa, Yoruba etc. in Nigeria.
Each of these communities strive hard to preserve it's own culture and traditions.
This evening cna TV Channel telecast an interesting on how Ainu community works hard to preserve It's culture and traditions. I tried to provide a link to the documentary but couldn't access it.
As a professuonal who worked in Africa as well as Cambodia (based in Phnom Penh), I found one such documentary featuring Nigerian community in Phnom Penh, Cambodia. Let me share the interesting documentary here.