Peter Turchin theorized that a major driver of the American Civil War was economic. Using his metrics for
civil conflict, he identified
elite overproduction and popular immiseration as forces that fueled the sectionalism that led to war. Between 1820 and 1860, average wages relative to higher incomes fell by more than 40 percent, while the expansion of the planter class threatened yeoman farmers. The rise of the
Free Soil Party,
Know-Nothing movement, and later the Republican Party reflected a distressed political environment. Recurrent financial crises, such as the
Panic of 1837, severe
state debt crises in the 1840s, and
Panic of 1857, added further accelerants. The destruction of the Southern planter elite allowed Northern industrialists and
political machines to consolidate control over the economy during the
Reconstruction Era and to establish a virtual monopoly on the American economy and political system through the
Gilded Age.