The Missouri Compromise did the following:
1) Officially made Maine a state in the US. This would be a state that does not allow slavery.
2)Officially made Missouri a state in the US. This would be a state that allows slavery.
3) Establishes the 36'30 line. This latitude/longitude line separated free and slave states/territories. Any state north of this line would NOT allow slavery. Any state south of this line would allow for slavery.
This compromise was in created in huge part due to Henry Clay and helped to temporarily solve the issue of slavery in new territories acquired by the US.
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