Ancient clans of Lanka Wikipedia
The indigenous people of Sri Lanka were known as Nagas and Yakkas.They ruled over the island of Sri Lanka during the pre-Vijaya era. The various clans of Sri Lanka and the mystical kingdom of Lanka was mentioned in the great epics of Mahabaratha, Mahavamsa, Manimekalai, Ramayana and Sangam. About the religion of the natives is known that the Naga culture were serpent-worshippers and the Yakka culture were demon worshippers. Even today, the Sri Lankan culture has some elements that originated from the culture of the Yakkas and Nagas. The majority of the native population were farmers and cattle herders. They had knowledge about healing arts (ayurvedic), built irrigation systems and temples. There were trade relations and royal intermarriage between the indigenous people of Sri Lanka and their neighbors in the South India kingdoms.
The era before the arrival of Prince Vijaya was not well documented so there is not much known of the previous native rulers of Sri Lanka. Ravana the mythical king of Lanka kingdom is considered the most famous and most powerful native king who ever reigned in Sri Lanka. The native rulers of Sri Lanka were later supplanted by the Indian rulers who came from Kalinga and South India.