The Missouri Compromise, (1820), was used for to balance the free slaves and the slaves that had no freedom, It allowed Missouri to enter as a slave state at the same time Maine entered as a free state, thus maintaining a balance in numbers of free and slave states, Fugitive Slave Law allowed southerners to go into Northerner states and retrieve former slaves. The Compromise overturned the Missouri Compromise and left the overall issue of slavery unsettled. Hope this helps
