Batticaloa was under the Sinhalese kings – in 1505 – and not under any Tamil king.

Around 1505 when the Portuguese took over the south and harassed Arab traders who were running businesses there. The Arabs complained to the Sinhalese King and the king gave them land on the East coast, where they still live today. This proves the East, Batticaloa and Trincomalee were also under the Sinhalese kings – in 1505 – and not under any Tamil king.

When the Dutch arrived in 1637 they signed a deal with the Sinhalese King to have berthing rights for their ships in harbours on the East coast, Trincomalee and Batticaloa during the monsoon rains, proving that the eastern costal regions belonged to the Sinhalese in 1637.- and not to any Tamil Kingdom ..

When in 1660 Robert Knox’s father’s ship “Anne” stopped over at the eastern port of Trincomalee , Sinhalese soldiers arrested them and took them to their Sinhalese King, proving that in 1660 the east was under a Sinhalese King. Robert Knox and his friend Stephen Rutland lived among the Sinhalese (mostly in Kandy ) for over 17 years. Robert Knox wrote “Robert Knox in the Kandyan Kingdom ” a book about the Sinhalese he met. Nothing about Tamils or any Tamil kingdom is mentioned.

Portuguese historian De Queyroz in “Conquest of Ceylon ” says “As long as Anuradhapure was the capital, the whole island was subject to one King – There were fifteen kinglets, Dinvaca, Valave, Putaloa, Trinquilimale, Batecaloa, Candea and Jaffnapatam”. ( Anuradhapura was the capital of Sinhalese Kings)

http://www.lankaweb.com/news/items/2009/10/02/the-myth-of-eelam-dream/