This detailed study (developed from the author’s 2013 PhD thesis at Sophia University, Japan) explores the variation in power centers during the middle period of Khmer history, ie after the end of the Angkorian centrality. It reflects the enduring struggle to keep alive the notion of a Khmer sovereignity in the face of its neighbors’ pressures.
The main sources of the work are the Rājabaṅsāvatār or Rapā Ksatr (Royal Chronicle, or better say Chronicles) — previously studied, in particular, by Etienne Aymonier, Adhémard Leclere, the Khmer historian Tran Ngia in the 1970s and, more recently, Mak Phoeun, Khin Sok or Michael Vickery –, the incriptions dating back from that time period, archaelogical evidence and a toponymical analysis (how the names of places, pagodas and chedei (stupas) referred to specific sovereigns). They all point to a fascinating mix of strategic concerns, political rivalries and material priorities leading to install centers of power southwards after the “abandonment” of Angkor as a political — but not religious — center.
So, what led to the decline and abandonment of Angkor? The author considers all the hypothesis advanced by historians, including the ‘natural calamity” factor. As for the datation of this major event, he remarks: “The date 1431 that most of scholars marked as the event that punctuated the fall of Angkor after a final battle against Ayutthaya, is only mentioned in the Annals of Ayutthaya “Hluong Prasoat.” However, the Khmer chronicles do not mention this date as the time when the city of Angkor was attacked and taken by Ayutthaya. The Cambodian Chronicles only state that the king Bañā Yāt decided to move the capital city to Basan (Srei Santhor), because the city was invaded very often by Ayutthaya, many of the Khmer people were taken to Ayutthaya, and some important provinces of the west were occupied by Siam. The Khmer people became weakened and oppressed by the effects of war, and the Khmer king thought that if he still stayed at Angkor, he and his people might face continued threats and domination. Therefore, the supposed date of 1431 as being the time when Angkor was sacked by Ayutthaya seems to have been influenced by the Siamese chronicle. Although, the setting of the date 1431 is confusing when one compares the Khmer chronicles and Siamese chronicles, the date has been conventionally used as the date of the shifting of the capital southwards. As mentioned above, the relentless Siamese invasion is one of the main factors for the decline, and it led to the relocation of the capital to the south. Most of the historians and other researchers in the different fields of study of Cambodia accept this theory.”
For the author, this event was above all the result of fundamental, cultural changes inside the Khmer society: “The pillars of the Angkor civilization were supported by the religious beliefs of Hinduism and Mahayana Buddhism. The monarchs being regarded as god-kings were able to command the dedication and loyalty of subjects to serve the throne as a divine obligation. The introduction of Theravada Buddhism in the 14th century to the Khmers had turned out to hurt sublimely the basic foundation of the Angkor Empire in the long run. The adoption of Theravada Buddhism had also a great effect on the language, literature, art and architect, and the political systems guiding the society.”
As for the shift to the southern parts of the Khmer srok (land), “the reasons for the changes of capital to Srei Santhor and Longvek-Oudong were political, logistic, and agricultural, or a mix of the three, and the reasons lean heavily on the subsistence level economic environment that increased agricultural productions would support. Therefore, the first factor is political, which is related to the invasion by Siam that caused the shift of the capital to the south. The second factor is that the need to change the capital was something logistic, and was based on a need to attain wealth through increasing the frequency and access to trade. The third is that increased agricultural output coupled with the resulting increase in the possibility of production of trade goods and specialty items was a good strategy for a growing population, regarding economy and wealth. In addition, with regard to governing, a decision had to be made about choosing a location where both farming and trade routes were more easily accessed.”
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Map of the Khmer capital cities, by the author