Soon after the departure of Buddhaghosa Dhatusena came to the throne and “held like Dhammasoka a convocation about the three Pitakas."[86] This implies that there was still some doubt as to what was scripture and that the canon of the Mahavihara was not universally accepted.  The Vetulyas, of whom we heard in the third century A.D., reappear in the seventh when they are said to have been supported by a provincial governor but not by the king Aggabodhi[87] and still more explicitly in the reign of Parakrama Bahu (c. 1160).  He endeavoured to reconcile to the Mahavihara “the Abhayagiri brethren who separated themselves from the time of king Vattagamani Abhaya and the Jetavana brethren that had parted since the days of Mahasena and taught the Vetulla Pitaka and other writings as the words of Buddha, which indeed were not the words of Buddha."[88] So it appears that another recension of the canon was in existence for many centuries.

Dhatusena, though depicted in the Mahavamsa as a most orthodox monarch, embellished the Abhayagiri monastery and was addicted to sumptuous ceremonies in honour of images and relics.  Thus he made an image of Mahinda, dedicated a shrine and statue to Metteyya and ornamented the effigies of Buddha with the royal jewels.  In an image chamber (apparently at the Abhayagiri) he set up figures of Bodhisattvas,[89] by which we should perhaps understand the previous births of Gotama.  He was killed by his son and Sinhalese history degenerated into a complicated story of crime and discord, in which the weaker faction generally sought the aid of the Tamils.  These latter became more and more powerful and with their advance Buddhism tended to give place to Hinduism.  In the eighth century the court removed from Anuradhapura to Pollannaruwa, in order to escape from the pressure of the Tamils, but the picture of anarchy and decadence grows more and more gloomy until the accession of Vijaya Bahu in 1071 who succeeded in making himself king of all Ceylon.  Though he recovered Anuradhapura it was not made the royal residence either by himself or by his greater successor, Parakrama Bahu.[90] This monarch, the most eminent in the long list of Ceylon’s sovereigns, after he had consolidated his power, devoted himself, in the words of Tennent, “to the two grand objects of royal solicitude, religion and agriculture.”  He was lavish in building monasteries, temples and libraries, but not less generous in constructing or repairing tanks and works of irrigation.  In the reign of Vijaya Bahu hardly any duly ordained monks were to be found,[91] the succession having been interrupted, and the deficiency was supplied by bringing qualified Theras from Burma.  But by the time of Parakrama Bahu the old quarrels of the monasteries revived, and, as he was anxious to secure unity, he summoned a synod at Anuradhapura.  It appears to have attained its object by recognizing the Mahavihara as the standard of orthodoxy and dealing summarily with dissentients.[92] The secular side of monastic life also received liberal attention.  Lands, revenues and guest-houses were provided for the monasteries as well as hospitals.  As in Burma and Siam Brahmans were respected and the king erected a building for their use in the capital.  Like Asoka, he forbade the killing of animals.