14. The Khmer Empire
The Khmer Empire once reigned over Southeast Asia, with Angkor as its magnificent capital and Angkor Wat as a lasting symbol. In the 15th century, Angkor was rapidly abandoned, marking a stunning decline after centuries of grandeur. Scholars cite ecological mismanagement—such as failed water systems—along with devastating wars and the rise of new maritime trade routes as key factors. The remnants of Angkor’s temples stand as silent witnesses to the swift and dramatic end of a remarkable civilization. Read more at Smithsonian Magazine.
