This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
A Cham attack on Angkor in 1178 opened a period of instability inside the Khmer Empire, one King Jayavarman VII resolved by founding a new capital and turning the empire's own state religion away from Hinduism toward Mahayana Buddhism. His wife, Indradevi, a devout Buddhist, is recorded as having encouraged the change, a shift carried out by the ruler who had just restored the empire's stability after the attack that had opened the crisis.
Angkor Wat itself, built decades earlier as a Hindu temple dedicated to Vishnu, was rededicated under the new state religion, and its Hindu sculpture was progressively replaced with Buddhist art across the generations that followed Jayavarman VII's own reign. The change at the temple was gradual rather than sudden, a rebuilding of the site's religious character in stages rather than a single act of conversion.
What this changed for the region's religious history was lasting rather than temporary: by the sixteenth and seventeenth centuries, Theravada Buddhism, not the Mahayana Buddhism Jayavarman VII had first promoted and not the Hinduism it had replaced, had become the settled religious framework of Angkor and the wider Khmer world, a position the tradition still holds today, centuries after Hinduism's own displacement from the site.