A fascinating map of Alexandria issued in 1845 by the noted map maker Thomas Sinclair documents an unusual period in the city’s history, when it was still included within the boundaries of the District of Columbia, but just before steps were initiated to retrocede the land area on the west bank of the Potomac back to the Commonwealth of Virginia.

The map was prepared by a young civil engineer, Maskell C. Ewing, who was an 1826 graduate of the U.S. Military Academy at West Point, N.Y. Ewing’s skills as a topographer and his attention to detail were considerable, and his documentation of Alexandria that year offers numerous clues to how the city had developed in the first century since its creation.

But the confluence of emerging geo-political and social issues in the region also foretold a future of vast opportunities and devastating threats. By 1845, Alexandria had officially been part of Washington, D.C. for less than 50 years, but the economic growth anticipated by its inclusion within the federal district fell short of expectations. Geographically, the district’s diagonal boundary line, visible here on the left side of the Jones Point Peninsula and proceeding to the rural wilderness beyond the angled turn of King Street at the top, slashed the southern downtown area into two parts without respect for the existing street grid or governance.

Although it was the expressed wish of George Washington that Alexandria would be included within the new capital, his extensive land holdings in the town he had helped create as a young surveyor prompted Congress to amend the Residence Act of 1791 to restrict the erection of all major federal buildings in the new capital to the Maryland side of the river.

This instantly stagnated Alexandria’s economy and caused even its extensive port facilities to surrender their strategic prowess to the competition upstream in Georgetown. The new Chesapeake & Ohio Canal, under construction between Georgetown and the Ohio River, had threatened to further erode Alexandria’s strategic importance even more, but in May 1830, Congress authorized a group of Alexandria businessmen to construct the Alexandria Canal, linking with the C&O seven miles to the north and allowing cargo boats to avoid unloading their goods at Georgetown and to proceed directly to Alexandria instead.

The extent of earth movement associated with the canal improvements needed to reach Alexandria’s shoreline can be seen on the right side of the map, where the inland watercourse bends sharply to meet the Potomac River, dropping boats 38 feet through a series of four locks. But by the time the canal was complete, only a year or so before this map was created, it was largely obsolete due to construction of the Baltimore & Ohio Railroad, which bypassed Alexandria altogether.

Alexandrians were further discouraged by their inclusion within the national capital for other reasons. Although slavery was still extant in Maryland and D.C. when this map was prepared, proposals to outlaw the trade throughout D.C. scared Alexandrians. The Duke Street slave trade that moved enslaved African Americans from Northern Virginia to the deep South was one of the city’s only thriving industries at the time, and the city relied heavily on slave labor as revenues floundered.

The 1834 failure of Congress to recharter the Bank of Alexandria only added to the town’s economic woes. Finally, the inability of D.C. residents to vote in national elections or be represented in Congress only further eroded Alexandrians’ confidence in their new governmental order.

When a referendum of residents to secede from the District and return to Virginia governance was held on Sept. 1 and 2, 1846, the vote was overwhelming in favor, 763 to 222, with a massive day-long celebration held in Alexandria on Sept. 19.

The vote would set the stage for the tumultuous changes to come to the city within the next decade and a half.

Out of the Attic is provided by the Office of Historic Alexandria. This article originally appeared in the May 26, 2016 Alexandria Times.