This animation shows the population density of U.S. counties between 1790 and 2010, showing the westward expansion of the country’s population.
At the moment, there are around 326 million people living in the United States, a country that’s 3.5 million square miles (9.8 million sq km) in land area.
But throughout the nation’s history, neither of these numbers have stayed constant.
Not only did the population boom as a result of births and immigrants, but the borders of the country kept changing as well – especially in the country’s early years as settlers moved westwards.
U.S. Population Density Over Time
From a big picture perspective, here is how population density has changed for the country as a whole over the last 200 years or so:
But today’s animated map, which comes to us from Vivid Maps, takes things a step further.
It plots U.S. population density numbers over the time period of 1790-2010 based on U.S. Census data and Jonathan Schroeder’s county-level decadal estimates for population. In essence, it gives a more precise view of who moved where and when over the course of the nation’s history.
Note: While U.S. Census data is granular and dates back to 1790, it comes with certain limitations. One obvious drawback, for example, is that such data is not able to properly account for Native American populations.