ABSTRACT
It was only in the twentieth century that the US became a predominantly urban nation. The year 1920 marks a significant shift. Ten years earlier, according to the 1910 Census, only 45.6 percent of the population lived in urban areas. By the time of the next Census, in 1920, the urban population was 51.2 percent of the total population. The population threshold used for classification of urban was very small. The US Census used, and still uses, a minimum population figure of 2,500, a value that includes places scarcely above the level of a small collection of dwellings. Even with this low threshold value, the US remained resolutely rural until 1920.
