Hello!
The answer is: June 1st, 1796.
Why?
In June 1st, 1796, Tennessee became part of the Union. The geographical area known as Tennesse today did belong to the Paleo Indians about 11000 or 12000 years ago.
In 1891 Tennesse was the last state leaving the Union, but at the end of the American Civil War, was the first readmitted state of the Union. Tennesse is known by the state that furnished more soldiers for the Union Army, even being compared with the entire Confederacy Army.
According to the last population census, Tennesse has a population of 6,700,000 people.
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