The Land and Its Early People. Prehistory – 1519.
Age of Contact. 1519-1689.
Spanish Colonial. 1689-1821.
Mexican Rule. 1821-1835.
Revolution and Republic. 1836-1845.
Early Statehood. 1845-1861.
Civil War and Reconstruction. 1861-1870.
Cotton, Cattle, and Railroads. 1850-1901.
The thing which was a major factor that threatened the major unity in the United States in the mid-19th century was:
<h3>The Great Depression</h3>
This refers to the period around 1929 in the United States which has a profound effect on the national economy.
This led to the failure of many banks, increase in unemployment and high deflation rates which all threatened the national unity.
Read more about Great Depression here:
brainly.com/question/441267
People had very little political freedom
