On the eve of its 1975 victory against the Lon Nol forces, the KCP was, in terms of personnel, ideological viewpoints, and factional loyalties, quite heterogeneous. Etcheson, in The Rise and Demise of Democratic Kampuchea, identifies six factions: the Pol Pot group (members of which he labels "Stalinists") internationalists (pro-Vietnamese elements who were based in Hanoi after 1954, and who returned to the country when the FUNK united front was declared in 1970) veterans of the leftist Khmer Issarak (who remained in the country after 1954, mostly in the southern and in western parts of the country) veterans of the Pracheachon Party founded in 1954 (which had contested Sihanouk's Sangkum openly until being driven underground in the 1960s) pro-Chinese or Maoist elements (including Paris-group intellectuals Hou Yuon and Hu Nim) and the pro-Sihanouk Khmer Rumdo (see Appendix B). Ben Kiernan, another analyst of Cambodia, identifies three factions: the Pol Pot faction, the pro-Vietnamese communists, and the adherents of the Chinese Cultural Revolution model. The roles of ideology and of conflicting party lines in factional struggles, however, should not be overemphasized. Behind doctrinal differences lay the dynamics of personal rivalry and the strong sense of patron-client loyalty that has always characterized Cambodian politics.

Although the Revolutionary Army of Kampuchea (RAK) was "reestablished" in July 1975 to bring all Khmer Rouge units formally under central authority, real control of regional armed forces remained in the hands of the zone party committee heads. The most important center of regional resistance to the Pol Potdominated party center was the Eastern Zone, comprising part or all of the old provinces of Prey Veng, Svay Rieng, Kandal, and Kampong Cham that adjoined Vietnam. Its leader was So Phim, a proVietnamese internationalist.

Differences between the Eastern Zone revolutionaries and the other Khmer Rouge were readily apparent by 1975. While the uniforms of Pol Pot loyalists and their allies were black, the uniforms of the Eastern Zone were a distinctive green. In addition, cadre behavior toward the civilian population in the Eastern Zone was generally exemplary. It seems that some of the Eastern cadres were sympathetic to Sihanouk refugee Molyda Szymusiak wrote that during the evacuation of Phnom Penh, a "Sihanouk Khmer" soldier advised her relatives (who were distantly related to the royal family) to accompany him to Prey Veng Province on Cambodia's southern border.

At least two coups d'état against the center were attempted--in July and in September, 1975. The latter incident involved Eastern Zone troops. After April 1975, Hou Yuon, one of the original Paris group, disappeared. His colleague, Hu Nim, who was tortured and killed in the Tuol Sleng detention center in 1977, indicated in his confession that Hou Yuon had been liquidated for opposing the extremism of the center's policies.

Pol Pot loyalists occupied most of the important positions in the new government that was formedf15 ed after the March 20, 1976, elections however, Vorn Vet, a pro-Vietnamese leader, was appointed second vice premier with responsibility over six ministry-level economic committees, and he also headed the special Phnom Penh capital zone. So Phim, a longtime rival of Pol Pot within the communist movement, was first vice president of the presidium and a member of the KCP Political Bureau. (The second vice president, Nhim Ros, was a Pol Pot loyalist who commanded the Northwestern Zone.) The year 1976 appears to have been a time initially of retreat for the faction led by Pol Pot. Many communists were alienated by his authoritarian behavior. Article 4 of the Constitution, "Democratic Kampuchea applies the collective principle in leadership and in work," apparently reflects this opinion. In relation to what had gone before and what was to come, policies during 1976 were moderate. The terror eased. Relations with Hanoi were placed on a friendlier footing. Trade and diplomatic relations were expanded.

On September 27, 1976, Pol Pot resigned as premier "for reasons of health." Nuon Chea, the pro-Vietnamese deputy premier, became acting premier. Little is known of the intense factional maneuvering that was occurring at this time, but by late October 1976, Pol Pot had regained his post. On October 22, his comeback was confirmed with his issuance of a statement in his capacity as prime minister condemning China's "counterrevolutionary Gang of Four," who had been arrested in Beijing on October 6.

The influence of China on Democratic Kampuchea's internal politics apparently was a crucial, though little understood, factor in Pol Pot's defeat of his pro-Vietnamese rivals. Etcheson and Kiernan have suggested, in separate articles, that radicals in the Chinese Communist Party may have backed pro-Vietnamese Internationalist elements in the KCP in 1976 because they were interested in preserving good relations with Hanoi. The fall of the radicals in October 1976, a month after Mao Zedong's death, brought in the moderates, led by Deng Xiaoping. As the subsequent break between Beijing and Hanoi shows, Deng was inclined to regard Vietnam as an agent of Soviet "hegemonism." Chinese support of the Pol Pot faction may have been a crucial element in its ability to triumph over the pro-Vietnamese communists in the fall of 1976. From an ideological standpoint, the pragmatic Deng Xiaoping and the ultra-radical Pol Pot were polar opposites, but from the geopolitical perspective, the post-Mao Zedong leadership recognized the value of having a well-armed Cambodian thorn in the side of Vietnam. Immediately after making his September 27, 1977, speech revealing the KCP's existence, Pol Pot, accompanied by Ieng Sary and Vorn Vet, visited Beijing, where he acknowledged the importance of Maoist thought to the Cambodian revolution. In early 1978, the Chinese sent substantial military aid, which included armor, artillery, and antitank guns.

Data as of December 1987