Alexandria County (extinct) was named for the town of Alexandria. It was formed from a portion of Fairfax County that had been ceded by Virginia in 1789 to the federal government for use as the site of the national capital. In 1801, the area officially became part of the District of Columbia, although Congress named it Alexandria County. The county was returned to Virginia in 1846, and in 1847 the General Assembly extended the commonwealth's jurisdiction over the locality. In 1920, the county name was changed to Arlington County.

Original Records at The Library of Virginia: Yes