He inherited his throne via palace intrigues in which a number of heirs died under mysterious circumstances.
His father, Singai Pararasasegaram, had two principal wives and a number of concubines.
According to a letter by Andre de Souza, ordered Cankili I on November 1544 the murder of his eldest son for converting to Catholicism.
[1][2] The son was buried on the spot he was killed, where a chapel was built that later on served as the foundation for the construction of the present St. Mary's Cathedral at Jaffna.
[3][4] Cankili I resisted all contacts with the Portuguese, maintained relationships with Kunjali Marakkar got assistance from and even massacred 600 – 700 Parava Catholics in the island of Mannar who were brought from India to Mannar by the Portuguese to take over the lucrative pearl fisheries from the Jaffna kings.