The county was formed in 1806 off of land that was split from Mason County. The present county (which was one of three that was split) was named after Meriwether Lewis who was an american explorer, soldier and a public administrator. You may know Meriwether Lewis best as the leader of the Lewis and Clark expedition in which their purposes were to explore the new land which was acquired in the Louisiana Purchase, establish trade with the native americans near the Missouri River and the Pacific Northwest. The county is really known for its really fine oak lumbering. Now with the county being a minimal of 485 miles above sea level, it also has a total area of 495 square miles and has a population count of 13,257 residents.