The importance of the Missouri Compromise in American history lies in its role in temporarily mitigating sectional tensions surrounding slavery. Enacted in 1820, the compromise admitted Maine as a free state and Missouri as a slave state, maintaining the balance of power in Congress. Additionally, it established the 36°30′ parallel as a dividing line for future states, with slavery prohibited to the north. While it offered a temporary resolution, the compromise ultimately highlighted the deepening divisions in the nation that would later culminate in the Civil War.