Madison County was formed on January 13, 1846. It has been self-governed since 1849. It was named after James Madison, the fourth President of the United States. Madison County is located in the U.S. state of Iowa. As of 2000, the population is 14,019. Its county seat is Winterset, and it is one of the five counties that make up the Des Moines-West Des Moines Metropolitan Statistical Area.