An animation of western expansion.
At the time of America's first Census in 1790, the country was just a cluster of states tilted on the eastern seabord, with Virginia as its most populous. In the two centuries since then, as America has grown in geography and population, its population and power centers have steadily drifted westward.
The below data visualization from Jonathan Hull illustrates that story in a surprisingly succinct 52 seconds. Borrowing from the typography of old-timey maps, Hull has produced a kind of timelapse of Census data by state spanning the full history of the federal head count. States are shown in blue and territories in green. The size of each state's abbreviation swells in proportion to its size in population (states in darker blue have a larger share of the U.S. population, states in lighter blue have a smaller share).
Only three states (Virginia, New York and then California) have ever held the designation of the most populous. Those states are bracketed in red. Meanwhile, the cartwheeling red star approximates the westward shifting center of the U.S. population:
Note how inconsequential California looks in 1870, and the moment, one century later, when it takes over from New York as the nation's largest state by population.