The twenty states that supported the Union were the following (with their capitals)
1. California – Sacramento
2. Colorado – Denver
3. Connecticut – Hartford
4. Delaware – Dover
5. Iowa – Des Moines
6. Illinois – Springfield
7. Indiana – Indianapolis
8. Kansas – Topeka
9. Maine – Augusta
10. Massachusetts – Boston
11. Michigan – Lansing
12. Minnesota – St. Paul
13. New Hampshire – Concord
14. New Jersey – Trenton
15. New York – Albany
16. Ohio – Columbus
17. Oregon – Salem
18. Pennsylvania – Harrisburg
19. Rhode Island – Providence
20. Wisconsin – Madison
These twenty states chose to remain loyal to the Union during the American Civil War by providing troops, military supplies, financial resources, and generally upholding the Federal government’s authority against the Confederate states. President Abraham Lincoln famously declared that the War was “maintained, on the part of the Union, for the cause of maintaining the nation’s full integrity”. In other words, these states were loyal to the Union, despite the pressure from the Confederacy to secede. The loyalty of these states was critical in winning the Civil War and preserving the Union.