Fairmont is a city in Marion County, West Virginia, United States. The population was 18,704 at the 2010 census. It is the county seat of Marion County.
Prior to the founding of Fairmont, the land that would become Marion County was part of Monongalia and Harrison County. In the 1700s, the earliest development of this area consisted of subsistence farming settlements. In 1789, Boaz Fleming, a Revolutionary War veteran, migrated to this area and purchased a 254-acre farm from Jonathan Bozarth. Oral history indicates that in 1808, Fleming made his annual trek to Clarksburg to pay his brother's Harrison County taxes. While in Clarksburg, Fleming attended a social gathering that included his cousin, Dolley Madison, wife of President James Madison. Fleming complained to Mrs. Madison about having to travel over a hundred miles each year from his home to pay his Monongalia County taxes and his brother's Harrison County taxes. Mrs.