Answer:
The Missouri Compromise was a legislation passed in 1820 that aimed to address the issue of the balance of power in the Senate between free and slave states. The problem arose because, as new states were admitted to the Union, the balance of power between free and slave states in the Senate was threatened. If a free state was admitted, it would give the North more power in the Senate, while if a slave state was admitted, it would give the South more power.
To solve this problem, the Missouri Compromise established that Missouri would be admitted as a slave state, while Maine would be admitted as a free state. This kept the balance of power between free and slave states in the Senate intact. In addition, the Missouri Compromise prohibited slavery in the remainder of the Louisiana Territory north of the 36°30' parallel, with the exception of Missouri. This effectively created a line dividing the North and South, with slavery allowed south of the line and prohibited north of it.
As a result of the Missouri Compromise, the South gained the admission of Missouri as a slave state, which helped to maintain their power in the Senate. However, the South also stood to lose if more free states were admitted in the future, as it would dilute their power in the Senate.
The South began to look to the land to the west of the borders of the U.S., in what was then part of Mexico, because they saw it as a potential source of new slave states. The South was concerned that the balance of power between free and slave states in the Senate would be threatened if more free states were admitted, and they wanted to ensure that they had enough representation in Congress to protect their interests. The land in what is now the southwestern United States was seen as a valuable resource for the South because it had a warm climate that was suitable for growing cotton, a labor-intensive crop that was in high demand at the time. The South hoped that by establishing new slave states in this region, they could maintain their power in the Senate and protect their economic interests.
However, the Missouri Compromise was not a permanent solution to the issue of the balance of power between free and slave states, and it ultimately contributed to the growing tensions between the North and South that eventually led to the Civil War. The compromise was seen as a temporary measure that merely delayed the inevitable conflict between the two sides, and it was eventually repealed with the passage of the Kansas-Nebraska Act in 1854, which allowed the people of those territories to decide whether or not to allow slavery.