Let me explain clearly. In India there is a state called TamilNadu(TN) which means “A country of tamil speaking people”.
It was never a part of India till the British Invasion. Tamil Nadu in the past was ruled by Chola kings for more that 5000 years and they became prominent during 900AD.
Raja Raja Cholan and his son Rajendra Cholan ruled Tamil Nadu, invaded many countries around TamilNadu and brought them under the control. Some of the countries invaded by them are Srilanka, Maldives, Burma, Cambodia, Thailand and Indonesia.
The cholas are the worshippers of Lord shiva, the hindu god.When they invaded Indonesia during 950 AD, they constructed hindu temples which led to the begining of hinduism in Indonesia.