In the 9th and 10th centuries AD, Pandya and Chola incursions into Sri Lanka culminated in the Chola annexation of the island, which lasted until the latter half of the 11th century CE.

The decline of Chola power in Sri Lanka was followed by the restoration of the Polonnaruwa monarchy in the late 11th century AD. In 1215, following Pandya invasions, the Tamil-dominant Arya Chakaravarthi dynasty established an independent Jaffna kingdom on the Jaffna peninsula and parts of northern Sri Lanka. The Arya Chakaravarthi expansion into the south was halted by Alagakkonara, a man descended from a family of merchants from Kanchipuram in Tamil Nadu. He was the chief minister of the Sinhalese king Parakramabahu V (1344–59 AD). Vira Alakeshwara, a descendant of Alagakkonara, later became king of the Sinhalese, but he was overthrown by the Ming admiral Cheng Ho in 1409 AD. The Arya Chakaravarthi dynasty ruled over large parts of northeast Sri Lanka until the Portuguese conquest of the Jaffna Kingdom in 1619 AD. The coastal areas of the island were taken over by the Dutch and then became part of the British Empire in 1796 AD. The English sailor Robert Knox described walking into the island’s Tamil country in the publication "An Historical Relation of the Island Ceylon", annotating some kingdoms within it on a map in 1681 CE. Upon arrival of European powers from the 17th century CE, the Tamils' separate nation was described in their areas of habitation in the northeast of the island.

The caste structure of the majority Sinhalese has also accommodated Hindu immigrants from South India since the 13th century AD. This led to the emergence of three new Sinhalese caste groups: the "Salagama", the "Durava" and the "Karava". The Hindu migration and assimilation continued until the 18th century AD.

Tamil emigrant communities
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