the Three Pagodas Pass, where they received formal settlement rights from the Siamese Governor of Kanchanaburi. Sometime between 1827 and 1839 the Siamese King Rama III established this area as a principality (mueang) and the Karen leader who governed the principality received the Siamese title of nobility Phra Si Suwannakhiri. During the second half of the 19th century, this Karen principality at the Burmese border became particularly important for the Siamese King Rama V (Chulalongkorn) in his negotiations with the British colonial power in Burma regarding the demarcation of their western border with Siam. At the beginning of the 20th century, when the modern Thai nation state was established, the Karen in Thung Yai lost their former status and importance. During the first half of the 20th century, external political influences were minimal in Thung Yai and the Karen communities were highly autonomous regarding their internal affairs. This changed in the second half of the 20th century, when the Thai nation state extended its institutions into the peripheral areas and the Karen re-appeared as chao khao or "hill tribes" on the national political agenda, as forest destroyers and illegal immigrants. Plans to protect the forests and wildlife at the upper Khwae Yai and Khwae Noi river grew in the mid-1960s. Due to strong logging and mining interests in the area, it was not before 1972 that the Huai Kha Khaeng Wildlife Sanctuary could be established, and Thung Yai resistance was even stronger. However, in April 1973 a military helicopter crashed near Thung Yai and revealed an illegal hunting party of senior military officers with family members, businessmen, and a film star, arousing nationwide public outrage which finally led to the fall of the Thanom-Prapas Regime after the uprising of 14 October 1973. After this accident and under a new democratic government, the area finally could be declared a wildlife sanctuary in 1974. After the military had taken power once again in October 1976, many of the activists of the democracy movement fled into peripheral regions of the country and some of them found refuge among the Karen people living in Thung Yai. During the 1960s, not only timber and ore, but also the water of the western forests as hydroelectric power resources became of interest for commercial profit and national development. A system of several big dams was planned to produce electricity for the growing urban centres. On the Khwae