From Ohio History Central
On February 16, 1810, the Ohio government authorized the creation of Madison County. The county was named in honor of James Madison, the fourth president of the United States. The county began to flourish during the 1830s, with the completion of the National Road through Ohio.
Madison County is located in west central Ohio. It is predominantly rural, with less than one percent of the county�s 465 square miles consisting of urban areas. The county seat is London. With a population of 8,771 people, London was the county�s largest community in 2000. The next largest urban area, Somerford Township, had only 6,975 residents that same year. Unlike most of Ohio�s predominantly rural counties, Madison County experienced an increase in population�8.5 percent�between 1990 and 2000, increasing the total number of residents to 40,213 people. The main reason for this increase was the large number of residents from Columbus, in nearby Franklin County, who sought to escape that city�s busyness by moving to more rural, neighboring counties. In recent years, Madison County�s population has declined by approximately 1.7 percent as residents moved back to Columbus or to other large cities. Many residents of Ohio�s rural communities are seeking better lives and more opportunities in the state�s cities. Madison County averages almost eighty-seven people per square mile.
Farming is the largest employer in Madison County, followed closely by manufacturing businesses and government positions. Service industries, such as health care and communications, rank a distant fourth. Over eighty-eight percent of the county�s acreage is farmland, with residents ranking second in soybean and third in corn production in Ohio. The London Correctional Facility employs many of the government workers. In 1999, the per capita income in the county was 21,782 dollars, with 8.7 percent of the people living in poverty.
Most voters in Madison County claim to be independents, yet in recent years, they have overwhelmingly supported Republican Party candidates at the national level.