Source: International Herald Tribune
BANGKOK: The collapse of Cambodia's great ancient city of Angkor may have been due to a massive drought nearly 600 years ago — not just rival Siamese forces and widespread deforestation as previously suspected, a researcher said.
Brendan M. Buckley said Tuesday that bands from tree rings that he and his colleagues examined show that Southeast Asia was hit by a severe and prolonged drought from 1415 until 1439, coinciding with the period during which many archeologists believe Angkor collapsed.
From the city of famed temples, Angkorian kings ruled over most of Southeast Asia between the 9th and 14th centuries. They oversaw construction of architectural stone marvels, including Angkor Wat, regarded as a wonder of religious architecture and designated a World Heritage Site by UNESCO.
While the 1431 invasion from Siam — what is now Thailand — has long been regarded as a main cause of Angkor's fall, archaeologists working at the sprawling temple site have suspected that ecological factors played a major part in its collapse.
http://www.iht.com/articles/ap/2009/02/18/asia/AS-Cambodia-Angkor-Downfall.php