When was the Yanbian Korean Autonomous Prefecture established in China?

August 30, 1955, the State Council abolished the Yanbian Korean National Autonomous Region, the establishment of Yanbian Korean Autonomous Prefecture. December 20, held the second session of the first people's congress of Yanbian Korean Autonomous Prefecture, Yanbian Korean Autonomous Prefecture was formally established. The people's government of the autonomous region (then called the people's committee) in yanji city.