In the last post, I discussed the low densities of American cities below the 36'30" line of latitude. One factor for this is their locations. Look at a map, San Francisco looks like it should be the spot for a large city, same with New York, Boston, even Charleston. Moving away from the coasts, the river and water intersections by Cincinnati, Cleveland, Chicago, Pittsburgh, Buffalo, Milwaukee, New Orleans, St. Louis, Seattle, and Portland also make decent sized cities in those locations seem very reasonable. And then considering the importance of water power to early manufacturing and milling, you can understand how cities developed near waterfalls at Minneapolis, Baltimore, Philadelphia, and Richmond.
Made by Man or by Mickey Mouse
So you had oceans, water intersections, and fall lines account for much of this country's urban growth, especially in its Northern half. So what happened to the south? Early San Francisco investors were concerned that San Diego would be their main in state rival, and overlooked LA, why did they miss it? Why did Atlanta, only the fourth largest city in its state before the Civil War, become the largest metro in the Southeast? Its downtown isn't even on the river! Charlotte also has the same odd relationship with its river, why did it get so large? Also, why the hell is there a city where Orlando is? Shouldn't Tampa Bay be much larger? Is Mickey really that powerful?
The technologies that defined American city growth up to about 1850 required certain physical traits. Cities had to accommodate the costs of making and moving goods with clipper ships, cotton gins, river barges, and the like. But as time has gone on, technology has advanced to the point that topography and proximity to water have mattered less. Essentially, technology has allowed large cities to form at what are essentially man made locations.
In the 1840s, Milwaukee grew over 10x, faster than Chicago, which was booming, but at a slower pace. Chicago ended the decade with a little under 30,000 people, Milwaukee a little more than 20,000. Both were still smaller than Cincinnati, Pittsburgh, and St. Louis, but were growing rapidly due to their locations on the Western side of the Great Lakes. Neither had rail connections to the east, and they could have ended up close competitors. But the 1850s were to rail construction what the 1990s were to fiber optics and Internet infrastructure, and by 1860, Chicago was sailing past Milwaukee. Rail essentially reduced the impact of the city's natural setting, and in the South, it allowed less-than-obvious places, like Atlanta and Charlotte, to surpass fall line cities like Augusta and Columbus, GA, ocean ports like Charleston and Savannah, and ultimately river cities like Memphis and New Orleans.
Ships to the North, Oranges to the South
This move away from natural settings went a step further as technology advanced. Look at a map of Southern California. The port by Coronado Island, San Diego, looks like a much more obvious place for a large city than an area of land 15 miles from any ocean, and adjacent to a river that had to be placed on top of concrete by the Army Corps of Engineers, in order to stop it from flooding in the winter, even though it ran dry in the summer. But that place, LA, grew way beyond its peer to the south.
LA's location was chosen by Mexican farmers who needed access to the river, and it was setup as a small agricultural community, not a booming Ocean port like San Francisco. And LA's original industry wasn't movies, Disney, or oil, but oranges. This was the same industry that launched another city in an odd spot for a city, Orlando. The underlying technology, refrigerated boxcars, allowed these oranges to be shipped to population centers across the country. These refrigerated boxcars, in turn, encouraged more investment in rail links to these cities, pushing their growth even higher. In 1890, 20 years before the first movie studio opened, and two years before the discovery of oil in Southern California, Los Angeles was already up to 50,000 people, 3x the size of nearby San Diego, which had been expected to become Southern California's answer to San Francisco.
From Refrigerated Boxcars to the Disney Monorail
Orlando never grew like LA did, but the mere fact that oranges and refrigerated boxcars allowed a city to pop up in such an odd place did impact Tampa, just as LA drew people away from San Diego. Tampa was a dense city in 1950, with over 6,500 ppsm, and without a growing city two hours east, could have blossomed into a much larger area. But regardless of what happened to Tampa, the location of Orlando, especially after Mickey and Goofy arrived, could barely be described as a natural setting for a city.
If you look at most growing regions and cities today, from Charlotte to Phoenix to Atlanta to Dallas to Orlando, they rely very little on water or their natural setting for growth, unlike New York, Boston or San Francisco in their boomtown days. It's easy to say this is all because of cars or something Congress did, but when people chose to haul Citrus to the Midwest or to haul the kids to Disney, I doubt they wrote the House of Representatives.