Professor Alexis Sanderson delivered a lecture on Khmer Śaivism and gave a three-day extensive reading and explanation of the introductory section of Abhinavagupta’s Tantrāloka for an audience of doctoral researchers and colleagues at the Center for Buddhist Studies at the University of California at Berkeley, October 2016.
Here is Professor Sanderson's description of his Lecture on Khmer Śaivism:
Of Śaivism, Pāñcarātrika Vaiṣṇavism and Mahāyāna Buddhism, the three Indic religions that flourished among the ruling and priestly élites of the Khmers up to the 14th century, Śaivism was predominant. We see this in the śaivization of the land through the creation of a large number of local Śivas bearing the names of Indian prototypes (a phenomenon not seen in the other two traditions), in the role of the Śiva Bhadreśvara of Vat Phu as a national deity and protector of the monarch, in evidence of the institutionalization of Śaivism as the religion of the state, and in traces of Śaiva inroads into Khmer Vaiṣṇavism and Buddhism.
Indian Śaivism was not static or homogeneous and Khmer Śaivism reflects some at least of this diversity and development over time. We see Pāśupata Śaivas of the Atimārga in the inscriptions of the seventh century and when the epigraphic record returns from the late ninth to the fourteenth we find that they have given way to Śaivas of the Mantramārga practising the Saiddhāntika and Vāma ritual systems. The evidence among the Khmers for all of these traditions, and also for that of the lay Śivadharma, will be considered, as will the evidence for the granting of Saiddhāntika Śaiva initiation to the Khmer monarch. It will also be shown that the Khmers’ importation of Śaivism was not continuous. It did not keep up with developments in India but preserved in the case of the Mantramārga an archaic form belonging to its earliest Indian phase, a form soon abandoned in India itself. This lack of continuous contact during the most creative phase of the Indian Mantramārga also explains the absence from the Khmer epigraphic and material evidence of large parts of the mature Mantramārga, most notably the cults of Bhairava and the Śākta Śaiva cults of goddesses. In line with developments in Sumatra and Java Khmer Buddhism seems to have maintained a more continuous line of communication, adopting, for example, elements of the late Tantric Buddhism that was the reflex of the Śākta Śaivism lacking among the Khmers.
The relationship between the Śaivism of initiates in both the Atimārga and the Mantramārga with the lay Śaivism of the uninitiated will also be considered. It will be argued that the differences between the Atimārga and the Mantramārga had little perceptible effect on the public aspects of the religion as embodied in the iconographic range of Śiva forms and ancillary deities in Śiva's temples. That iconographic program, which concerns the laity, has no place in either the Atimārga or the Mantramārga. It has its own history, which neither system did much to modify. The richness of the Khmer iconic and epigraphical evidence is in this as in other respects highly instructive not only for the student of the nature of Indic culture beyond India but also for those seeking to clarify the history of religion in India itself.
Finally, I shall consider some evidence that the Khmer version of Indian Śaivism includes some elements that appear to have no Indian prototypes.