Washington DC facts: the U.S. capital’s story

Washington DC facts start with a city that is also a federal district: Washington, D.C., is the capital of the United States and its only federal district. Its name, its borders, and its role were all set in the nation’s earliest years, and the city still carries that original design in its streets and institutions.

How was Washington, D.C. created?

Washington, D.C., was founded with the Residence Act, adopted on July 16, 1790. On September 9, 1791, the city was named in honor of President Washington, and the federal district was named Columbia at the same time. Columbia was the female personification of the American nation, which is why the district’s full identity links both Washington and Columbia.

Pierre Charles L'Enfant designed Washington, D.C., in 1791. His plan gave the city its distinctive layout, including quadrants that meet at the Capitol Building. That structure is part of what makes the city easy to map and easy to recognize, especially around the center of federal power.

Why is the Capitol so important?

The Capitol became central to the city almost immediately because the 6th Congress started meeting there in 1800, while the building was still unfinished. That moment tied the new capital to the work of government from the start, with lawmakers gathering in the building that would become one of the city’s best-known landmarks.

Washington, D.C., hosts the White House, the U.S. Capitol, the Supreme Court Building, and multiple federal departments and agencies. Those institutions make the city the place where executive, legislative, and judicial power all sit within the same district.

The city also holds many national monuments and museums. Among them are the Jefferson Memorial, the Lincoln Memorial, and the Washington Monument. These sites give the capital a visual identity that reaches far beyond politics and into national memory.

How many people live in Washington, D.C.?

As of the 2020 census, Washington, D.C., had a population of 689,545. During the workweek, the daytime population rises to more than one million, reflecting how many people travel into the city for government, business, and related work.

That population pattern fits a city built around institutions that draw people in every weekday. The resident count and the daytime count tell two parts of the same story: one city functions as both a home and a working center for the country’s capital life.

What gives the district its special status?

The district’s status has been shaped by federal law and representation rules. The Twenty-third Amendment gave the district three presidential electors, creating an important role in presidential elections. Later, Congress enacted the District of Columbia Home Rule Act in 1973, providing for an elected mayor and a 13-member council.

Walter Washington became the district’s first elected and first black mayor in 1975. That election marked a new phase in the city’s government, with local leadership established through the structure Congress had created.

Why does Washington, D.C. matter beyond politics?

Washington, D.C., is home to 177 foreign embassies, adding an international layer to its national role. The city’s federal buildings, monuments, museums, and embassies all share the same space, making the district a place where American government and world diplomacy meet.

From the Residence Act in 1790 to L'Enfant’s 1791 plan, from the unfinished Capitol in 1800 to home rule in 1973, Washington, D.C., has grown through specific decisions that shaped its name, layout, and government. It remains both a city and a federal district, built to symbolize and house the nation’s power.

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