Winnsboro is a town in Fairfield County, South Carolina, United States. The population was 3,550 at the 2010 census. It is the county seat of Fairfield County. Winnsboro is part of the Columbia, South Carolina Metropolitan Statistical Area.
Based on archeological evidence, this area of the Piedmont was occupied by various cultures of indigenous peoples from as early as the Archaic period, about 1500 BC. Blair Mound is a nearby archeological site and earthwork likely occupied 1300-1400 AD, as part of the late Mississippian culture in the region.
Several years before the Revolutionary War, Richard Winn from Virginia moved to what is now Fairfield County in the upland or Piedmont area of South Carolina. His lands included the present site of Winnsboro. As early as 1777, the settlement was known as "Winnsborough" since he was the major landowner. His brothers John and Minor Winn joined him there, adding to family founders.
The village was laid out and chartered in 1785 upon petition of Richard and John Winn, and John Vanderhorst. The brothers Richard, John and Minor Winn all served in the Revolutionary War.