It is best known as the stage for a massacre of protesters in June 4, 1989.
Some student protesters decided to protest in Tienanmen Square about two weeks earlier. Their demands were disjointed and confused. Some reports suggest they wanted democracy for everyone, others report that they didn't want the ignorant peasants to have a say, just educated people like them. In other words they wanted to share power with the dictatorial power bloc.
Regardless of whether they wanted democratic rights for everyone, or just for themselves, the government at the time didn't want to share power. They hoped the demonstration would go away, but it didn't. In fact it grew and grew, to the point where it looked as though a large percentage of the population was about to take the streets much like the People Power revolution of The Philippines which brought down the corrupt Marcos dictatorship.
There were internal maneuverings within the Chinese power bloc, and Jiang Zemin saw an opportunity to prove he was the strong-man, and ordered tanks into Tienanmen Square to massacre the protesters. He was later promoted to President of China, suggesting the strategy worked.
The number of people who were actually killed cannot be determined. Estimates on Western media started at over 2000, went down to 1000 over a few days, and finally settled around several hundred. The Chinese government has never admitted that anyone was killed in the incident.
The next morning as the Tanks were pulling out and driving down the Avenue of Eternal Peace, a man stood in front of a row of 4 tanks, and this was filmed by a TV cameraman hiding in building nearby. The tanks stopped in their tracks, and then tried to drive around him. It is one of the most poignant images of the 20th century.
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