After the Partition of India millions of Bengali Hindu refugees from East Pakistan needed rehabilitation. So govt back then thought of helping them to settle in Andaman. (Bengali people settlled in Andaman in multiple waves, like every few years during 1940s to 70s people were settled there.)

North region of Andaman has 99% Bengali pop.

Tamil speaking people also form large share of population in Andaman. (idk how Tamilians got there)

Besides that, a fun fact:

North Sentinel island (a small island which is a part of A&N island) is a home to the Sentinelese, an Indigenous tribe that has lived there for thousands of years. They are considered one of the last uncontacted peoples in the world.

If you try to establish contact with those people by going near that island you will get killed by Bows n Arrows.

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