Louisiana was admitted into the Union on April 30, 1812 becoming the 18th state to join the Union.Mississippi was admitted into the Union on December 10, 1817 becoming the 20th state to join the Union.
The Missouri Compromise allowed two new states to be admitted. The two states that were admitted are Maine and Missouri.
No states were admitted in 1800.
CA became a state in 1850 and the law was called The Compromise of 1850.
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States admitted in the 20th century: Oklahoma, New Mexico, Arizona, Alaska, and Hawaii.
New states can be admitted into the United States through a process outlined in the U.S. Constitution. This process involves Congress passing a law to admit the new state, followed by the President signing the law.
Before the Civil War, there was a perfect balance between "slave" states and "free" states. Neither side could budge the other, and no new states could be admitted to the Union without a vote of the Congress - more specifically, the Senate. So new states were admitted in pairs, one slave and one free, to preserve the balance. If one new "slave" state had been admitted to the Union, the majority of slave state senators would have been able to outvote the "free" state senators and admit more "slave" states. The balance was shattered when the southern states seceded from the United States, and the Civil War settled the issue - at the cost of a half-million dead.
New York City
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New York
Same as now except for Alaska (admitted 1959) and Hawaii (1960). Therse were the first new states admitted since New Mexico and Arizona in 1912.