Why the United States built Washington

A Congress chased out of town

In June 1783 Revolutionary War soldiers who hadn’t been paid marched on Philadelphia, where the Confederation Congress was meeting, and surrounded its building demanding their money.^[5][6] Pennsylvania’s government did little to protect it, and Congress left for Princeton, New Jersey, meeting there from 26 June.^[5]

The framers of the Constitution remembered it. They gave Congress the power to govern its own seat directly, outside any state, so that it would never again depend on a state’s militia for its safety.^[6] The Constitution lets Congress exercise “exclusive Legislation in all Cases whatsoever, over such District (not exceeding ten Miles square) as may, by Cession of particular States, and the Acceptance of Congress, become the Seat of the Government of the United States.”^[4]

The dinner-table bargain

The first Congress under the Constitution met in New York City from March 1789.^[1] It deadlocked on two questions at once. One was where to put the permanent capital. The other was Alexander Hamilton’s plan for the federal government to take over the states’ war debts, which the North wanted, because its states still owed most of theirs, and the South opposed, because its states had paid much of theirs off.^[7]

On 20 June 1790 Thomas Jefferson had Hamilton and James Madison to dinner. Madison agreed to stop blocking the debt plan and to bring some southern votes with him; in return the capital would go south, to the Potomac, after ten years in Philadelphia.^[7][3]

Congress passed the Residence Act, “An Act for Establishing the Temporary and Permanent Seat of the Government of the United States”, on 16 July 1790.^[3] Congress moved to Philadelphia that December, and sat there until May 1800.^[1] Philadelphians spent the decade lobbying to keep it, even offering President Washington an elaborate mansion.^[6]

Moving in

Work on the Capitol had begun in 1793, and cost more than expected.^[2] Congress met there for the first time on 17 November 1800.^[1] President John Adams, who moved into the President’s House that month, addressed Congress in a Senate chamber that was crowded, leaky and unheated.^[2][6] One senator wrote that the city needed “houses, cellars, kitchens, well informed men, amiable women, and other little trifles of this kind.”^[2]

Not quite ten miles square

The Residence Act left the exact site to President Washington. He wanted a square ten miles on a side along the Potomac, taking in the ports of Georgetown in Maryland and Alexandria in Virginia.^[8] He set it on its corner, like a diamond. Andrew Ellicott surveyed it in 1791, with Benjamin Banneker, a self-taught free Black astronomer, doing the measurements and astronomical calculations. The first boundary stone went in that year at Jones Point, the square’s southern corner, and a stone marked every mile of the 40-mile boundary. 37 of the 40 are still there.^[8] About 31 of the district’s 100 square miles came from Virginia.^[9]

Alexandrians cheered joining the district, expecting it to bring them business.^[10] It didn’t. The 1791 act that set the boundaries barred any public buildings south of the Potomac, so the federal city grew on the Maryland side.^[11] Residents of the district lost their votes in Congress and for president.^[9] After the War of 1812, Baltimore and New York overtook Alexandria as ports.^[10] A canal the town built to reach the Chesapeake and Ohio Canal at Georgetown didn’t pay off either.^[11]

Slavery was the other reason. By the 1830s Alexandria was the largest slave-trading centre in the United States.^[11] Abolitionists were lobbying Congress to end slavery and the slave trade in the district, and white Alexandrians who profited from it, slave traders among them, wanted the town back under Virginia’s laws.^[10] Black Alexandrians feared losing the schools and freedom of assembly they had in the district. After the return, schools did close.^[10]

In July 1846 Congress passed an act to give Alexandria County back to Virginia if its voters agreed. They did, by 763 votes to 222, and President Polk declared the act in force that September.^[12][11] Virginia formally took the land back on 13 March 1847.^[11] Three years later, as part of the Compromise of 1850, Congress banned the slave trade in what was left of the district.^[13]

That is why the district looks the way it does on a map: a diamond with its southwestern side cut off along the Potomac. The land that went back is now Arlington County, which was called Alexandria County until 1920, plus part of the City of Alexandria.^[14] Whether Congress could constitutionally give away part of the district has never been settled. In 1875 the Supreme Court turned away an Alexandria County taxpayer’s challenge to the return without deciding that question.^[15]