Which pro-reformer and Communist leader set off the protests in Tiananmen Square when he died ?

The Tiananmen Square protests of 1989 eventually ended in the violent suppression of protesters on June 4th. Hundreds of civilians were killed during the protests.

Because the protests had been sparked by the death of Hu Yaobang, the government determined that any public discussion of Hu and his legacy could destabilize China by renewing debate about the political reforms that Hu supported. Because of the public association with Hu and the 'Tiananmen Massacre', Hu Yaobang's name became taboo on the mainland, and the Chinese government censored any mention of him in the media.

Hu Yaobang (1915-1989) was a high-ranking official of the People's Republic of China. He held the top office of the Communist Party of China from 1981 to 1987, first as Chairman from 1981 to 1982, then as General Secretary from 1982 to 1987.

He joined the Chinese Communist Party in the 1930s, and rose to prominence as a comrade of Deng Xiaoping. During the Cultural Revolution (1966-1976), Hu was purged, recalled, and purged again by Mao Zedong.

Because Hu pursued a series of economic and political reforms under the direction of Deng, it made him the enemy of several powerful Party elders, who opposed free market reforms and attempts to make China's government more transparent. A day after Hu's death (heart attack), a small-scale demonstration commemorating his legacy occurred. A week later, the day before Hu's funeral, some 100,000 students marched on Tiananmen Square.