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.
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.
[4] Today Runan County falls under the jurisdiction of the prefecture level city of Zhumadian.