The 50th state
US is not a state it is a country!
1998
Uh... Mexico is not a state. It is a country.
Chicago never became a state. Chicago is a city in the state of Illinois, which became the 21st state on December 3, 1818.
The City of Chicago is not now, and never has been, the capital of the State of Illinois.
December 14th, 1819 it was admitted as the 22nd U.S state but it later left the Union to become a Confederate state
2015
I personally don't know.
The date is November 16, 1907.
March 3, 1820.
Colorado became a state on august 1, 1876.