New Technology Leads to Bigger Cities
In the 1800s, the United States was still a very young nation, trying to solidify its identity. The Industrial Revolution began in Great Britain, a fast development of society following the introduction of machines. The United States was slower than Great Britain to fully embrace the changes. Yet key technological developments caused a rapid growth in American urban areas.

The urbanization of the united states quickened due to technology improvements

without innovations in food production the factories could not have grown so quickly

the trend quickened after 1860 and continued throughout the 21st century as well

by 2007, more Americans lived in or near cities than they did in rual areas