Angkor Wat, built during the early years of the 12th century by Suryavaram II, honors the Hindu god Vishnu and is a symbolic representation of Hindu cosmology. But within 200 years, the powerful Khmer civilization mysteriously collapsed. Theories of its downfall abound but nothing is definite. You see, aside from limited temple inscriptions no written records of the great Khmer Empire survived its demise.
Angkor Wat was constructed as a Hindu temple, it has served as a Buddhist temple since Buddhism became Cambodia’s dominant religion in the 14th century.
Centuries passed and dense jungle swallowed the magnificent Khmer temples and cities. But in the 18th Century, French explorers rediscovered the ruins, initiating 150 years of intense scholarship that continues today.
Mouhot is often mistakenly credited with "discovering" Angkor, although Angkor was never lost — the location and existence of the entire series of Angkor sites was always known to the Khmers and had been visited by several westerners since the 16th century. Mouhot mentions in his journals that his contemporary, Father Charles Emile Bouillevaux — a French missionary based in Battambang — had reported that he and other western explorers and missionaries had visited Angkor Wat and the other Khmer temples, at least five years before Mouhot. Father Bouillevaux published his accounts in 1857: "Travel in Indochina 1848–1846, The Annam and Cambodia". Previously, a Portuguese trader Diogo do Couto visited Angkor and wrote his accounts about it in 1550, and the Portuguese monk Antonio da Magdalena had also written about his visit to Angkor Wat in 1586.