Progression of political boundaries in DC. Animation from Wikipedia reproduced under GNU Free Documentation License.

Most readers of this blog are probably already aware that “Washington” and “District of Columbia” haven’t always been synonyms. Just in case, here’s how it works:

During the colonial period the farmers and plantation owners of Virginia and Maryland needed port cities to ship goods to/from Europe and to serve as regional markets. The most obvious place for a port was at the fall line of the Potomac River, the highest point upstream (and therefore most convenient to farmers) where ocean-going ships could travel. Small ports were founded at Alexandria in 1730 and Georgetown in 1745. The cities of Alexandria and Georgetown grew rapidly and were officially chartered in 1749 and 1751, respectively. They grew and prospered, so that by the 1800 census Alexandria was the 22nd largest city in the young United States, and Georgetown the 32nd. By comparison, the 22nd and 32nd largest metropolitan areas today are Pittsburgh and Columbus. For their day, Alexandria and Georgetown were big cities.

In 1790 Congress mandated that the new capital city be located along the Potomac. By 1791 the boundaries of the would-be District of Columbia were settled, to intentionally include the existing cities of Alexandria and Georgetown. L’Enfant began his famous work that same year. In 1800 the US government was moved to Washington, which began to grow in earnest. In 1801 the District of Columbia Organic Act was passed by Congress, officially creating the DC territory, which included two separate counties and three separate cities. Alexandria County was south of the Potomac River and included the City of Alexandria, as well as unincorporated rural land in what is now Arlington. Washington County was north of the river and included the City of Washington, the City of Georgetown, and surrounding unincorporated areas.

The two county / three city arrangement continued until 1846, when Alexandria County was retroceded to Virginia. For the next 25 years “Washington County” was synonymous with “District of Columbia”, but the cities of Washington and Georgetown remained separate, and all development in Anacostia or north of what is now Florida Avenue remained unincorporated. It was not until 1871 that Washington County and all its component cities was consolidated to form the unified City of Washington, DC. Since then, “DC” and “Washington” have been synonyms.

Of course it’s impossible to know for sure, but I like to imagine what the fall line of the Potomac would look like today had it not become the seat of government. Would the region have faded into the history books like Middleborough, MA (23rd biggest city in 1800, and it hasn’t grown much since), or would it have become a large, dynamic metropolitan area on its own terms? Given the importance and size of the Potomac River economy it seems safe to suggest that there would be some sort of dual-core “twin cities” metropolitan area here today, but just how big? Dallas / Fort Worth or Fredericksburg / Falmouth?