According to the mahavansa, yakkhas confined to the center of the Island and Naga dominated the northern and western parts in sixth century B.C. Therefore North of the Island was called Nagadipa. Mr.Kanagasabai,author of "Tamils 1800 Years Ago', mentioned that Yakkhas were the acient 'Yuh chi' a yellow race that emigrated from central of Asia into India through the Himalayan and eventually spread over the whole of bengal and ultimately move to Ceylon.

The Fa hien, monk had told there were no human inhabitations, but was occupied by Nagas and spirits, with which the merchants of various countries carried on a trade. The spirits never showed themselves ,they simply set forth their precious commodities ,with indications of the price attached to them, while merchants made their purchases according to the price.

Nagas was so called because they were serpent-worshippers. Archaeologist conjectured that the name was derived from the fact that their head covering was in the shape of the hood of a hydra-headed cobra.

Aryan emigrated to Ceylon and spread their power across the country. Eventually Naga and Yakksha population was reduced because of Aryans.