Stafford County is a county located in the Commonwealth of Virginia. It is approximately 40 miles (64 km) south of Washington, D.C. It is part of the Northern Virginia region, and the D.C area. It is one of the fastest-growing and highest-income counties in America. As of the 2020 United States census, the population sits at 156,927. Its county seat is Stafford.

Located across the Rappahannock River from the City of Fredericksburg and Spotsylvania County, Stafford County is part of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area. In 2006, and again in 2009, Stafford was ranked by Forbes magazine as the 11th highest-income county in the United States. According to a Census Bureau report released in 2019, Stafford County is currently the sixth highest-income county in America.

For thousands of years, various native cultures succeeded each other in their territories along the Potomac River and its tributaries. By the time of English colonization, there were 32 Algonquian-speaking Native American tribes in the present-day coastal Tidewater Virginia area, including those of the Patawomeck and numerous tribes that were part of the Powhatan Confederacy. The former small tribe, still centered in Stafford County, was recognized by the state of Virginia in 2010.

The Indigenous' first recorded encounter with Europeans in this area was in 1608, with John Smith of the Jamestown Settlement. During a time of recurring tension between the early English colonists and the local natives, the colonists led by Samuel Argall captured Chief Powhatan's daughter, Pocahontas, while she was living with her husband, Kocoum, at the Patawomeck town of Passapatanzy. The colonists took her from Passapatanzy, located in the eastern part of what is now Stafford County, to a secondary English settlement, known as Henricus (or Henrico Town). During her captivity there, Alexander Whitaker converted Pocahontas to Christianity. She took the name "Rebecca" at her baptism. Rebecca/Pocahontas married English colonist John Rolfe on April 5, 1614, in Jamestown. Their mixed-race descendants were among the First Families of Virginia.

The English colonial government of Virginia imposed its own order on the land and peoples. In 1664 it established Stafford County from territory previously part of Westmoreland County (which had been created from Northumberland County in 1653). It was named after Staffordshire, England. As originally delineated, Stafford County included a much larger area than its current borders. As population grew, the following counties and jurisdictions were created: Arlington, Fairfax, and Prince William counties, and the City of Alexandria. It is part of the area now considered Northern Virginia.

George Washington spent much of his childhood in the lower part of the county at his family's home Ferry Farm, which at the time was part of King George County and was along the Rappahannock River across from Fredericksburg. Colonial Forge High School was built on a tract of land owned in colonial times by his father Augustine Washington. George Mason, another Founding Father, also lived in Stafford during his formative years.

Aquia Church, built in 1757, is unusual among local structures for having been designed on the plan of a Greek cross rather than the more standard Roman Cross design. In addition, Aquia Church has a rare three-tiered pulpit; it has been designated as a National Historic Landmark. The Episcopal church continues to be active today.

Stafford County industry and resources were important to the colony and early nation. During the Revolutionary War, the Stafford ironworks furnished arms for the colonial rebel soldiers. Aquia Creek sandstone, quarried from Government Island, was used to build the White House and the U.S. Capitol.