During the Civil War, the term "Copperheads" referred to Northern Democrats who opposed the war and advocated for an immediate peace settlement with the Confederacy.

This group emerged in the North, criticizing President Abraham Lincoln's administration and its military policies, which they viewed as overly aggressive. Copperheads believed that continued fighting would lead to unnecessary bloodshed and that negotiations should take precedence. Their opposition often put them at odds with more ardent war supporters, and they were seen as a divisive force within the Union, contributing to tensions in Northern society during the conflict.