For those interested in Loudoun History of people freed prior to the Civil War you might want to read about the Lucas Heaton Collection of Letters online: http://www.loudounmuseum.org/letters.html
and The Waterford Foundation:
http://www.waterfordva.org/tour/history/shtml

The information both genealogical and historical contained in these two web sites are immense in value to African American researching Loudoun County, regarding the freedom of people of color.