Who is most associated with the concept of popular sovereignty during the debates over slavery?

The concept of popular sovereignty, which is the idea that the authority of the government is created and sustained by the consent of its people, is most closely associated with Stephen A. Douglas during the debates over slavery. Douglas advocated for this principle as a solution to the contentious issue of whether new territories should permit slavery. He believed that the residents of these territories should determine for themselves whether to allow slavery or not, thus enabling a democratic process.

This approach was prominently featured during the debates surrounding the Kansas-Nebraska Act of 1854, where Douglas's support for popular sovereignty meant that the settlers of Kansas and Nebraska could vote on the legality of slavery in their territories. This concept was significant because it aimed to reduce sectional tensions by allowing local decision-making, though in practice it led to conflicts exemplified by "Bleeding Kansas."

Understanding why Douglas is linked to popular sovereignty allows one to see the broader implications of this idea in the context of American political debates over slavery, as it highlighted a fundamental conflict between federal authority and states’ rights, an issue that became increasingly contentious during the antebellum period.