A decade of chaos and political upheaval in China with its roots in a factional dispute over the future of Chinese socialism. Oblique criticisms of Mao Zedong in the early 1960s prompted him to retaliate against this threat to his ideology-led position from more pragmatic and bureaucratic modernizers with ideas closer to the Soviet Union. Unable to do so in the Communist Party, he utilized discontented students and young workers as his Red Guards to attack local and central party officials, who were then replaced by his own supporters and often had army backing. Liu Shaoqi, State Chairman of China since 1959 and Mao's heir-apparent, lost all his government and party posts and Lin Biao became the designated successor. The most violent phase of the Cultural Revolution came to an end with the Ninth Party Congress in 1969, but its radical policies continued until Mao's death in 1976.