Formation Date: 1920
Formed From: Fairfax County
Previous Names: Alexandria County, Virginia from 1789 to 1801, Alexandria County, District of Columbia from 1801 to 1846, Alexandria County, Virginia from 1846 to 1920

Arlington County was originally named Alexandria County. It was formed from a part of Fairfax County that was ceded to the U.S. government in 1789 but was returned to Virginia in 1846. The county name was changed in 1920 to Arlington, the name of the Custis family mansion (former home of Robert E. Lee), which is located in the county. Its area is 25 square miles, and the county seat is Arlington. The population is 189,453 according to the 2000 census.

Original Records at The Library of Virginia: Yes