History › Middle ages
Khmer Empire and Angkor Wat
c. 802–1431; Angkor Wat built c. 1113–1150· Empire, kingdom or state· Asia
Well documentedSolid records, physical evidence or scientific consensus.
A Southeast Asian empire centered on Angkor in Cambodia, whose kings built Angkor Wat, the world's largest religious monument.
See it on the History map →What happened
Around 802 King Jayavarman II declared himself universal ruler, founding a state that came to dominate much of mainland Southeast Asia. Kings built temple-mountains as models of Mount Meru, home of the gods. Suryavarman II built Angkor Wat for the Hindu god Vishnu. Huge reservoirs and canals managed monsoon water for rice. Greater Angkor sprawled over about 1,000 square km, with perhaps 750,000 people (estimates vary). Siamese armies sacked it in 1431.
Why it matters
It shows how Indian religion and kingship took root in Southeast Asia, and how water engineering could sustain a giant city in the tropics.
How we know
Stone inscriptions in Sanskrit and Old Khmer; Chinese envoy Zhou Daguan's account of 1296–97; airborne laser (lidar) surveys since 2012 revealing city grids hidden under the forest.
Still debated
Why Angkor declined is debated: Siamese attacks, a shift of trade to the coast, or decades of drought and flooding that broke its water system.
Connections (2)
▸Gupta Empire: India's classical golden age built early Hindu temples, a tradition echoed at Khmer Empire and Angkor WatMostly agreed
The connection
Gupta-era India produced some of the first stone Hindu temples, with a sanctuary for the god's image and, later, towers symbolizing Mount Meru. Indian traders and priests carried Hindu and Buddhist ideas, Sanskrit and temple design to Southeast Asia. Khmer kings adopted Sanskrit titles and god-king rituals, and Angkor Wat's towers echo the same sacred-mountain idea.
When and how
India, about 400–600; Southeast Asia from the 400s onward, through the Funan and Chenla states that came before Angkor.
How sure are we?
Sanskrit inscriptions in Cambodia from the 600s onward; shared temple layouts and imagery; scenes from Indian epics like the Ramayana carved at Angkor Wat.
Debates and open questions
How the ideas traveled is debated: did Indian settlers bring them, or did local rulers pick and adapt Indian forms? Most scholars now stress local choice.
▸Khmer Empire and Angkor Wat turned, by the 1200s, to the teachings of The Buddha (Siddhartha Gautama)Well documented
The connection
Most Khmer kings had worshipped Hindu gods, but Jayavarman VII (reigned 1181–about 1218) was a devout Mahayana Buddhist. He built the Bayon temple, with its huge smiling stone faces, and hospitals across the empire. By the 1300s most people had adopted Theravada Buddhism, still Cambodia's main religion, and Angkor Wat itself became a Buddhist shrine.
When and how
Angkor, Cambodia, late 1100s–1200s under Jayavarman VII; Theravada Buddhism spread from Sri Lanka and the Mon lands of Burma and Thailand in the 1200s–1300s.
How we know
Jayavarman VII's own inscriptions, including his hospital edicts; Buddhist imagery at the Bayon; Zhou Daguan's 1296 description of yellow-robed monks.
Debates and open questions
Why ordinary people shifted to Theravada is debated; the Bayon's faces may show a bodhisattva, the king himself, or both.