Prince George’s County, also known as P.G. County, is a county in the U.S. state of Maryland, bordering the eastern portion of Washington, D.C. As of the 2010 U.S. Census, the population was 863,420, making it the second-most populous county in Maryland, behind only Montgomery County. Its county seat is Upper Marlboro. It is one of the richest African American-majority counties in the United States, and is also one of the highest-income counties in the United States.Prince George’s County is included in the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area. Due to its proximity to Washington, D.C. the county also hosts many U.S. governmental facilities, such as Joint Base Andrews, a U.S. military airbase, as well as the headquarters of the United States Census Bureau.EtymologyThe official name of the county, as specified in the county's charter, is "Prince George’s County, Maryland". The county is named after Prince George of Denmark (1653–1708), the consort of Anne, Queen of Great Britain, and the brother of King Christian V of Denmark and Norway. The county's demonym is Prince Georgian, or "PGer" more informally, and its motto is Semper Eadem ("Ever the Same"), a phrase used by Queen Anne. Prince George's County is frequently referred to as "P.G." or "P.G. County", an abbreviation which is the subject of debate, some residents viewing it as a pejorative and others holding neutral feelings toward the term or even preferring the abbreviation over the full name.