1. Kentucky was formed from the western part of Virginia in 1792.
2. Tennessee was formed from the southwestern part of North Carolina in 1796.
3. Louisiana was formed from the southern part of the Louisiana Territory in 1812.
4. Maine was formed from the northern part of Massachusetts in 1820.
5. Mississippi was formed from the western part of Alabama and the southern part of the Mississippi Territory in 1817.
6. Illinois was formed from the western part of the Indiana Territory in 1818.
7. Alabama was formed from the western part of Georgia and the eastern part of the Mississippi Territory in 1819.
8. Missouri was formed from the eastern part of the Missouri Territory in 1821.
9. Arkansas was formed from the southern part of the Missouri Territory in 1836.
10. Michigan was formed from the eastern part of the Michigan Territory in 1837.
11. Florida was formed from the eastern part of the Spanish colony of Florida in 1845.
12. Iowa was formed from the eastern part of the Iowa Territory in 1846.
13. Wisconsin was formed from the eastern part of the Wisconsin Territory in 1848.
14. California was formed from the western part of the Mexican Cession in 1850.
15. Minnesota was formed from the eastern part of the Minnesota Territory in 1858.
16. Oregon was formed from the northern part of the Oregon Territory in 1859.
17. Kansas was formed from the eastern part of the Kansas Territory in 1861.
18. West Virginia was formed from the western part of Virginia in 1863 during the American Civil War.
19. Nevada was formed from the western part of the Utah Territory in 1864.
20. Nebraska was formed from the eastern part of the Nebraska Territory in 1867.
21. Colorado was formed from the western part of the Kansas Territory and the eastern part of the Utah Territory in 1876.
22. North Dakota was formed from the eastern part of the Dakota Territory in 1889.
23. South Dakota was formed from the western part of the Dakota Territory in 1889.
24. Montana was formed from the western part of the Montana Territory in 1889.
25. Washington was formed from the western part of the Washington Territory in 1889.
26. Idaho was formed from the northern part of the Idaho Territory in 1890.
27. Wyoming was formed from the western part of the Dakota Territory and the eastern part of the Idaho Territory in 1890.
28. Utah was formed from the western part of the Utah Territory in 1896.
29. Oklahoma was formed from the western part of the Indian Territory and the western part of the Oklahoma Territory in 1907.
30. New Mexico was formed from the eastern part of the Arizona Territory and the western part of the New Mexico Territory in 1912.
31. Arizona was formed from the western part of the Arizona Territory in 1912.
32. Alaska was formed from the Department of Alaska in 1959.
33. Hawaii was formed from the Territory of Hawaii in 1959.