<P> To 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, and to exercise like Authority over all Places purchased by the Consent of the Legislature of the State in which the Same shall be, for the Erection of Forts, Magazines, Arsenals, dock - Yards and other needful Buildings; </P> <P> James Madison, writing in Federalist No. 43, also argued that the national capital needed to be distinct from the states, in order to provide for its own maintenance and safety . The Constitution, however, does not select a specific site for the location of the new District . Proposals from the legislatures of Maryland, New Jersey, New York, and Virginia all offered territory for the location of the national capital . Northern states preferred a capital located in one of the nation's prominent cities, unsurprisingly, almost all of which were in the north . Conversely, Southern states preferred that the capital be located closer to their agricultural and slave - holding interests . The selection of the area around the Potomac River, which was the boundary between Maryland and Virginia, both slave states, was agreed upon between James Madison, Thomas Jefferson, and Alexander Hamilton . Hamilton had a proposal for the new federal government to take over debts accrued by the states during the Revolutionary War . However, by 1790, Southern states had largely repaid their overseas debts . Hamilton's proposal would require Southern states to assume a share of Northern debt . Jefferson and Madison agreed to this proposal and in return secured a Southern location for the federal capital . </P> <P> On December 23, 1788, the Maryland General Assembly passed an act, allowing it to cede land for the federal district . The Virginia General Assembly followed suit on December 3, 1789 . The signing of the federal Residence Act on July 16, 1790, mandated that the site for the permanent seat of government, "not exceeding ten miles square" (100 square miles), be located on the "river Potomack, at some place between the mouths of the Eastern - Branch and Connogochegue". The "Eastern - Branch" is known today as the Anacostia River . The Connogocheque (Conococheague Creek) empties into the Potomac River upstream near Williamsport and Hagerstown, Maryland . The Residence Act limited to the Maryland side of the Potomac River the location of land that commissioners appointed by the President could acquire for federal use . </P> <P> The Residence Act authorized the President to select the actual location of the site . However, President George Washington wished to include the town of Alexandria, Virginia within the federal district . To accomplish this, the boundaries of the federal district would need to encompass an area on the Potomac that was downstream of the mouth of the Eastern Branch . </P>

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