There continues to be some debate over the fall of Angkor. The fall of Angkor has been attributed to a variety of factors, of both human and natural origin.
Human factors Military defeat The main reason for the fall of Angkor, especially according to Thai historians, is the Suphannaphum dynasty attack in 1431, which caused the Khmer to abandon Angkor and to retreat south-eastwards. Some believe that
Champa warriors from Southeast Asia may have sacked the city for its wealth.
Collapse of the hydraulic city Command of water played an important role in the rise and fall of Angkor, and scholars using satellite technology are only now beginning to fathom the true size and achievement of medieval Khmer society. Once abandoned after the reign of
Suryavarman II, stagnating reservoirs attracting mosquitoes may have been the cause spreading
malaria as this was also the period in which this disease was introduced in Southeast Asia. Groslier argues the fall of Angkor was partly brought on by an imbalance in the ecosystem that was caused by the extension of irrigated rice fields and hydraulic cities into formerly forested land in Cambodia, and was therefore an ecological crisis induced by mankind. A more
Malthusian argument that with excessive population growth, Angkor was unable to feed its own population which led to social unrest and eventually societal collapse.
Crisis of faith Some scholars have connected the decline of Angkor with the conversion of the
Khmer Empire to
Theravada Buddhism following the reign of
Jayavarman VII, arguing that this religious transition eroded the Hindu concept of kingship that underpinned the Angkorian civilization. According to Angkor scholar
George Coedès, Theravada Buddhism's denial of the ultimate reality of the individual served to sap the vitality of the royal personality cult which had provided the inspiration for the grand monuments of Angkor. The vast expanse of temples required an equally large body of workers to maintain them; at
Ta Prohm, a stone carving states that 12,640 people serviced that single temple complex. Not only could the spread of Buddhism have eroded this workforce, but it could have also affected the estimated 300,000 agricultural workers required to feed all of them. On the other hand, a new religious fervor was growing among the Siamese who came to believe that they had the moral authority as well as the self-confidence and the public support to challenge Khmer rule as the moral order of Angkor declined.
Natural factors Southeast Asian drought of the early 1400s Southeast Asia suffered a severe drought in the early 1400s. The
East Asian summer monsoon became very fickle in the decades leading up to the fall of Angkor in the fifteenth century. Brendan Buckley suggests this drought dried out Angkor's reservoirs and canals, which in turn, led to its precipitous decline and foreign invasion. == Aftermath ==