  the dark ages of cambodia covers the history of cambodia from the fifteenth to the nineteenth century, a period of continued decline and territorial loss. cambodia enjoyed a brief period of prosperity during the sixteenth century because its kings, who built their capitals in the region southeast of the tonlÃ© sap along the mekong river, promoted trade with other parts of asia. this was the period when spanish and portuguese adventurers and missionaries first visited the country. but the siamese conquest of the new capital at longvek in 1594 marked a downturn in the country's fortunes and cambodia became a pawn in power struggles between its two increasingly powerful neighbors, siam and vietnam. vietnam's settlement of the mekong delta led to its annexation of that area at the end of the seventeenth century. cambodia thereby lost some of its richest territory and was cut off from the sea. such foreign encroachments continued through the first half of the nineteenth century because vietnam was determined to absorb khmer land and force the inhabitants to accept vietnamese culture. ==cambodia's struggle for survival, 1432â1867== ===post-angkor period===  thumb|right|the cambodian flag before 1863. the more than four centuries that passed from the abandonment of angkor around the mid-15th century to the establishment of a protectorate under the french in 1867 are considered by historians to be cambodia's "dark ages", a period of economic, social, and cultural stagnation when the kingdom's internal affairs came increasingly under the control of its neighbors, the thai (siam) and the vietnamese. by the mid-19th century, cambodia had become an almost helpless pawn in the power struggles between siam and vietnam and probably would have been completely absorbed by one or the other if france had not intervened, giving cambodia a colonially dominated "lease on life." fear of racial and cultural extinction has persisted as a major theme in modern cambodian thought. the process of internal decay and foreign encroachment was gradual rather than precipitous and was hardly evident in the fifteenth century when the khmer were still powerful. following the fall of angkor thom, the cambodian court abandoned the region north of the tonlÃ© sap, to siam, never to return except for a brief interlude in the late sixteenth century. by this time however, the khmer penchant for monument building had ceased. previously established faiths such 
19th_century_in_Cambodia History_of_Cambodia