What idea promoted the belief that individual territories could determine their own slavery status?

The belief that individual territories could determine their own status regarding slavery is encapsulated in the concept of popular sovereignty. This idea emerged during the mid-19th century as a compromise in the contentious debates over the expansion of slavery into newly acquired territories. Advocates of popular sovereignty argued that the settlers in those territories should have the right to vote and make their own decisions about whether to permit slavery or not, rather than having that decision imposed by Congress or the federal government.

This doctrine was notably applied during the debates surrounding the Kansas-Nebraska Act of 1854, which effectively allowed the inhabitants of those territories to decide their own approach to slavery. The prevalence of popular sovereignty reflected a broader democratic impulse during this period, promoting the notion that rights and governance should derive from the consent of the governed.

In contrast, other concepts like state sovereignty pertain to the autonomy of the states rather than individual territories deciding on issues like slavery. Territorial rights might encompass broader impingement on the lives and politics of inhabitants, and federal authority refers to the power held by the national government, which would typically impose uniform laws across states and territories. Thus, popular sovereignty distinctly aligns with the idea of localized decision-making regarding slavery.