In 1820 an agreement called the Missouri Compromise was reached. The compromise allowed Missouri to come into the Union as a slave state and Maine would be a free state.
Congress drew an imaginary line across the middle of the United States running from the east coast to the Pacific Ocean. This imaginary line separated the states into free and slave states. Any new state entering the Union that was south of the line would be a slave state. Any state north of the line would enter the Union as a free state.
Maine became a state in 1820. Missouri became a state in 1821. For the next 15 years no states entered the Union. From 1836 to 1850 six states were admitted:
In 1850 California asked to be admitted to the Union. The Missouri Compromise had cut California in half. Congressmen argued over whether California should enter the war as a free or slave state.
Henry Clay, the man who worked out the Missouri Compromise, came out of retirement to try to work out another compromise. The new agreement was called the Compromise of 1850. In this compromise Northern California entered the Union as a free state.
The Compromise of 1850 added some new laws. Buying and selling slaves in Washington, D.C. was outlawed. The people living in Washington, D.C. could still own slaves, but could not buy or sell new ones. In the South the land received from Mexico was broken up into two states, New Mexico and Utah. In these states the settlers could decide for themselves whether they wanted slavery or not.
The South got a new law called the Fugitive Slave Law which said that any slaves escaping from the south to freedom in the north should be...