Washington, D.C.

Washington, D.C., officially the District of Columbia and commonly known as simply Washington or D.C., is the capital city and federal district of the United States. The city is split from Virginia to its southwest by the Potomac River and shares land borders with Maryland to its north and east. It was named after George Washington, a Founding Father and the first president of the United States. The district is named for Columbia, the female personification of the nation.

The U.S. Constitution in 1789 called for the creation of a federal district under exclusive jurisdiction of the U.S. Congress. As such, Washington, D.C., is not part of any state, and is not one itself. The Residence Act, adopted on July 16, 1790, approved the creation of the capital district along the Potomac River, and is considered the city's founding date. In 1800, when the capital was moved from Philadelphia, the 6th Congress started meeting in the then-unfinished Capitol Building, and the second president, John Adams, moved into the newly finished White House. In 1801, the District of Columbia, formerly part of Maryland and Virginia and including the existing settlements of Georgetown and Alexandria, was officially made the federal district; initially, the city was a separate settlement within the larger district. In 1846, Congress shrank the district when it returned the land Virginia had ceded, including the city of Alexandria. In 1871, it made the whole district into one municipality. There have been several failed efforts to make the district into a state since the 1880s, including a statehood bill that passed the House of Representatives in 2021 but was not adopted by the U.S. Senate.

Designed in 1791 by Pierre Charles L'Enfant, the city is split into quadrants that meet at the Capitol Building, with 131 neighborhoods overall. As of the 2020 census, the city's population was 689,545. During the workweek, commuters from the city's Maryland and Virginia suburbs raise the city's daytime population beyond one million. The Washington metropolitan area, which includes parts of Maryland, Virginia, and West Virginia, is the country's seventh-largest metropolitan area, with a 2023 population of 6.3 million residents. A locally elected mayor and 13-member council have governed the district since 1973, though Congress retains the power to overturn local laws. Washington, D.C., residents do not have voting representation in Congress, but elect a single non-voting congressional delegate to the U.S. House of Representatives. The city's voters choose three presidential electors in accordance with the Twenty-third Amendment, passed in 1961.

Washington, D.C., anchors the southern end of the Northeast megalopolis. As the seat of the U.S. federal government, the city is an important world political capital. The city hosts buildings that house federal government headquarters, including the White House, U.S. Capitol, Supreme Court Building, and multiple federal departments and agencies. The city is home to many national monuments and museums, located most prominently on or around the National Mall, including the Jefferson Memorial, Lincoln Memorial, and Washington Monument. It hosts 177 foreign embassies and the global headquarters of the World Bank, International Monetary Fund, Organization of American States, and other international organizations. Home to many of the nation's largest industry associations, non-profit organizations, and think tanks, the city is known as a lobbying hub, which is centered on and around K Street. It is also among the country's top tourist destinations; in 2022, it drew an estimated 20.7 million domestic and 1.2 million international visitors, seventh-most among U.S. cities.

The Algonquian-speaking Piscataway people inhabited present-day Washington, D.C. and lands around the Potomac River when Europeans first arrived and colonized the region in the early 17th century. The Nacotchtank, also called the Nacostines by Catholic missionaries, maintained settlements around the Anacostia River in present-day Washington, D.C. Conflicts with European colonists and neighboring tribes ultimately displaced the Piscataway people, some of whom established a new settlement in 1699 near Point of Rocks, Maryland.

During the American Revolution and Revolutionary War, nine cities served as capitals to the Continental Congress and under the Articles of Confederation. Following independence, New York City served briefly as the first capital following adoption of the Constitution before the capital returned to Philadelphia, where it remained from 1790 to 1800.

On October 6, 1783, after the Pennsylvania Mutiny of 1783 forced the capital to move briefly from Philadelphia to present-day Princeton University in Princeton, New Jersey, Congress resolved to consider a new location for it. The following day, Elbridge Gerry of Massachusetts moved "that buildings for the use of Congress be erected on the banks of the Delaware near Trenton, or of the Potomac, near Georgetown, provided a suitable district can be procured on one of the rivers as aforesaid, for a federal town".

In Federalist No. 43, published on January 23, 1788, James Madison argued that the new federal government would need authority over a national capital to provide for its own maintenance and safety. The Pennsylvania Mutiny of 1783 emphasized the need for the national government to not rely on any state for its own security.