IV. Ceylon (Lankavamsa) Buddhism
This is the most important period in the history of the spread of Buddhism to Thailand, for it witnessed the introduction to that country of that form of Buddhism which remains dominant there until today.
About 1153 A.D. (B.E. 1696) Parakramabahu the Great (1153-1186 A.D.) became king of Ceylon, known in ancient days as Lanka. A powerful monarch and a great supporter of Theravada Buddhism, Parakramabahu did much to spread and consolidate the Dhamma of the Lord in his island kingdom. He it was who caused (according to some scholars of Southern Buddhism) the Seventh Buddhist Council[3] to be held under the chairmanship of Kassapa Thera, of Dimbulagala in order to revise and strengthen the Doctrine and the Discipline (Dhamma and Vinaya).