1920
The 1920 Census was the Fourteenth. The Census Bureau provides a list of the 100 largest cities in that year.
| Rank | City | State | Population | Notes |
| 1 | New York | New York | 5,620,048 | |
| 2 | Chicago | Illinois | 2,701,705 | |
| 3 | Philadelphia | Pennsylvania | 1,823,779 | |
| 4 | Detroit | Michigan | 993,078 | The rise of the automobile industry in the Detroit area propelled its growth substantially between 1910 and 1920, doubling its population in only 10 years. |
| 5 | Cleveland | Ohio | 796,841 | |
| 6 | St. Louis | Missouri | 772,897 | |
| 7 | Boston | Massachusetts | 748,060 | |
| 8 | Baltimore | Maryland | 733,826 | |
| 9 | Pittsburgh | Pennsylvania | 588,343 | |
| 10 | Los Angeles | California | 576,673 | Los Angeles makes the top ten for the first time. |
Read more about this topic: Largest Cities In The United States By Population By Decade