Dynastic changes are not an uncommon feature in history. In the history of Sri Lanka they have been especially common and have sometimes taken place in such a rapid succession that one might form the impression of their being a recurrent feature. One observes the succession of the Moriyas by the Lambakaṇṇas, followed by the Pāṇḍyas and the Kāliṅgas. Usually such changes have been the result of the weakness of the central political authority, internal discord, factional disputes, and other such decisive forces which provided excellent conditions and ideal opportunities for ambitious kings, particularly from the sub-continent, to invade the island. Sometimes they have been caused by less hostile circumstances, at least in their initial stages, such as appeals for intervention by rulers to outside powers. There seem to have been certain special forces and features that marked the changes that occurred in the late medieval period. We shall be concerned here with a discussion of those forces with a view to understanding the special features of the process of change, the manner in which a comparatively insignificant clan of foreign descent acquired power and rose to the highest ranks of the governing élite, and also the forces that brought about its downfall. The question, “Why were the new élite unable to gain sovereign power when it was just within their grasp?” will engage our special attention.