The Khmer Empire
Learn about the Khmer Empire — the Southeast Asian civilization that built Angkor Wat, the largest religious monument on earth, and mastered hydraulic engineering.
The Khmer Empire (802–1431 CE), centered in modern Cambodia, was the dominant power in Southeast Asia for over six centuries and the builder of one of humanity's most extraordinary architectural achievements: Angkor Wat. At its peak in the 12th and 13th centuries, the Khmer capital at Angkor was one of the largest pre-industrial cities in the world, with a population that may have exceeded 750,000.
The empire's power rested on a sophisticated hydraulic system — an enormous network of reservoirs (barays), canals, and channels that captured monsoon rains and distributed water for year-round rice cultivation. This infrastructure supported dense populations and funded the construction of hundreds of temple complexes, including the incomparable Angkor Wat, originally dedicated to the Hindu god Vishnu and later converted to Buddhism.
Khmer civilization synthesized Indian religious and political concepts — Hinduism, Buddhism, Sanskrit literature, the concept of the god-king (devaraja) — with local traditions to create something distinctly Southeast Asian. Its influence spread across modern Thailand, Laos, and Vietnam. The empire's decline in the 15th century remains debated, but likely involved the breakdown of the hydraulic system, Thai military pressure, and shifts in maritime trade routes.