Which legislation determined whether slavery would be permitted in the territories of the Louisiana Purchase?

The Missouri Compromise of 1820 established the framework for determining whether slavery would be permitted in the territories of the Louisiana Purchase. This legislation was significant because it sought to maintain a balance between free and slave states as the nation expanded westward. Specifically, it admitted Missouri as a slave state while simultaneously admitting Maine as a free state to preserve this balance. Furthermore, the compromise established the 36°30′ parallel as the line dividing future free and slave territories in the Louisiana Purchase. This line effectively restricted slavery in the northern portions of the acquired territory, while allowing it in the southern areas, thereby setting a precedent for future territorial governance regarding the issue of slavery.

While the Kansas-Nebraska Act also dealt with the issue of slavery in territories, it came later and introduced the concept of popular sovereignty, allowing the settlers of each territory to decide for themselves whether to allow slavery. The Compromise of 1850 sought to resolve disputes following the Mexican-American War and included multiple measures regarding slavery, but it was not specifically focused solely on the Louisiana Purchase territories. The Fugitive Slave Act was part of the Compromise of 1850 and primarily dealt with the recapture of escaped slaves, rather than determining the legality of slavery in new territories. Thus