Anne Arundel County, also notated as AA or A.A. County, is located in the U.S. state of Maryland. As of the 2020 United States census, its population was 588,261, an increase of just under 10% since 2010. Its county seat is Annapolis, which is also the capital of the state. The county is named for Anne Arundell (c. 1615/1616–1649), Lady Baltimore, a member of the Arundell family in Cornwall, England, and the wife of Cecilius Calvert, 2nd Baron Baltimore (1605–1675), founder and first lord proprietor of the colony Province of Maryland. The county is part of the Central Maryland region of the state. Anne Arundel County is included in the Washington–Baltimore–Arlington combined statistical area.