What did the Missouri Compromise determine regarding slavery?

The Missouri Compromise, enacted in 1820, established a significant framework regarding the expansion of slavery in newly acquired territories. Specifically, it allowed for the admission of Missouri as a slave state while simultaneously introducing a crucial restriction: slavery was prohibited in the northern portion of the Louisiana Purchase, particularly in areas north of the 36°30′ parallel. This boundary effectively created a line that delineated free and slave territory in the western lands acquired from France.

Thus, the correct answer accurately reflects that slavery was indeed not allowed in the northern regions of the Louisiana Purchase. The compromise was a critical attempt to maintain a balance between free and slave states in the Union, seeking to reduce sectional conflict over the issue of slavery in emerging states and territories.