Louisiana, Indiana, Mississippi, and Illinois were all admitted into the Union between the years 1810 and 1820. The Northwest Ordinance had barred slavery from the territories north of the Ohio River. However, the areas that had been acquired in the Louisiana Purchase did not have a policy. This would all have to change when Missouri and Alabama both sought statehood in 1819. However, Missouri wanted to become a slave state. If its statehood were approved it would become the first slave state west of the Mississippi River. At the same time it would upset the numerical balance between slave and free states. It would not take long before the politicians realized that the issue was the type of situation that would require compromise. However, no one seemed to want to compromise.
Before long, New York Representative James Tallamadge introduced an amendment to the Missouri legislature that prohibited the introduction of more slaves into the territory. In addition, the amendment mandated the emancipation(freeing) of all Missouri born slaves when they reached the age of 25. Tallamadge's amendment launched an intense debate over slavery that would leave Congress deadlocked for more than a year, with the House of Representatives in favor and the Senate opposed. The Southerners were infuriated with Tallamadge's attempt to outlaw slavery in the territories. Many threatened secession from the Union. They stated that according to the Constitution they had the right to protect their property and that slaves were property. They also asserted that they had the right to take their slaves anywhere they wanted to in the territories, and that they would protect that right under any circumstances. Eventually, the Southerners tried to link Maine's statehood as a free state to Missouri's admission as a slave state. This idea angered Northerners. The debate became more and more impassioned until Representative Thomas Cobb of Georgia shouted at Tallamadge, “If you persist, the Union will be dissolved. You have kindled a fire which all of the waters of the ocean cannot put out, which seas of blood can only distinguish.”
The idea of allowing both states to enter the Union at the same time at least solved the problem of maintaining an equal balance of free and slave states. Before long, Senator Jesse Thomas of Illinois offered an amendment that prohibited slavery into the Louisiana Territory north of 36' 30', which was the southern border of Missouri. Few liked the idea, and the Northerners continued to fight the amendment. Then, on February 26, 1821, Speaker of the House Henry Clay's ambiguous language was adopted by the House. Clay stated that the anti-black clause in Missouri's constitution should never be construed as violating the rights of any citizen. The Missouri Compromise passed the House a week later, and before any opposition could emerge Clay quickly passed the legislation over to the Senate. Henry Clay would forever be known as the “Great Compromiser.” The Constitution of our country was in danger, and Henry Clay had saved it without bloodshed. Unfortunately, the question of weather or not Congress had the authority to abolish slavery had not been resolved, and would not for another 40 years. Years later, President Lincoln would remark that Henry Clay had made a difference. The fact that the Missouri Compromise limited the expansion of slavery would eventually have a positive effect as the free states would soon have a majority in the Senate. Then in 1854, the Compromise would be repealed by the Kansas-Nebraska Act, which in turn would ignite the anti-slavery movement.