The British signed a treaty with the Kandyan Adigars (minsters) handing over Sinhalé to the British in return for their guaranteeing various rights including the primacy of Buddhism.
It soon became evident that the "Kandyan convention" was a sham which was not being respected by the British.
In this the Portuguese were supported by low-caste tamils who had been converted to Christianity already during the co-habitation of Sankili-I with the Portuguese.
However, Mudliyar Attapattu who had been dispatched by the King of Kandy (Senerat) with an army of 10,000 defeated the the Portuguese soon after, as documented then by Joao Ribeiro and more recently by Tikiri Abeysinghe, (Jaffna under the Portuguese ISBN 955-1131-70-1).
The name Taprobana is attributed to Megasthenes in the 4th century BCE.