In ancient times, this area was called "the middle of the world" (), since it was the center of government for
Yu province and lay at the heart of the
Nine Provinces. The Duke of Zhou (), the most influential statesman of the early Zhou dynasty, visited Runan many times and termed it as the center of the land. During the
Han dynasty, it contributed the most officials to the central government of any commandery, and was
ancestral home to the immensely influential Ru'nan
Yuan clan. In former times Runan County was at various times called
Ancheng County () and
Ruyang County (), and
Caizhou ()., amongst others. During the
Zhou dynasty (1,045-256 BC), the vassal
State of Dao fell within the borders of the county. The town was the site of a major battle, the
siege of Caizhou, in the
war between the
Mongol Empire and
Jurchen Jin dynasty.
Emperor Aizong, the Jurchen ruler, had fled to Caizhou after the Jin capital of
Kaifeng was
captured by the Mongols. He committed suicide in Caizhou and his successor,
Emperor Mo, was killed in the besieged town. The Jin dynasty ended in Runan in 1234. ==Administrative divisions==