Obion was later established in 1824 and organized the following year. It was named for the Obion River, which flows through the county and is a tributary of the nearby Mississippi River. The word “Obion” is believed to be derived from a Native American word meaning “many forks,” or from an Irish trapper named O’Brien. The original finding of the county was due to the expansion of railroads coming through the south. Today, the county has a total area of 556 square miles with a population count of 30,267 residents.