The Missouri Compromise of 1820 was a legislative agreement that regulated the extension of slavery in the United States. It allowed Missouri to enter the Union as a slave state, but prohibited slavery in the northern portion of the Louisiana Territory above the 36°30' latitude line.
Arkansas became a state on June 15, 1836, after the Missouri Compromise had already been in effect for 16 years. However, the Missouri Compromise indirectly affected Arkansas' becoming a state in the following ways:
The Missouri Compromise established a precedent for admitting new states in pairs: one free and one slave. Arkansas was admitted as a slave state, paired with Michigan, which was admitted as a free state in 1837.
The Missouri Compromise made clear the line between free and slave territories, which helped to prevent conflicts over the expansion of slavery into new states. This likely helped Arkansas gain admission to the Union without significant controversy over the slavery issue.
The Missouri Compromise also helped to maintain the balance of power between free and slave states in Congress, which was a critical consideration in admitting new states. By admitting Arkansas as a slave state, the number of free and slave states remained equal at 12 each, preserving the balance of power in the Senate.
Overall, the Missouri Compromise played a role in shaping the conditions under which Arkansas was admitted to the Union as a slave state, and helped to prevent significant controversy over the issue of slavery during the admission process