|Monument to 8th Ill. Cavalry at Gettysburg|
Three regiments from Illinois fought at Gettysburg:
8th Regiment, Illinois Cavalry
This regiment was mustered in 1861 along the Fox River in St. Charles.
12th Regiment, Illinois Cavalry
The 12th was mustered in Springfield but also contained two companies known as the McClellan Dragoons who organized in Chicago.
82nd Regiment, Illinois Infantry
Organized in Springfield, this regiment consisted mostly of German, Scandinavian and Jewish immigrants.
Do you have ancestors who fought in the Civil War? I had at least three Civil War ancestors whose regiments fought at Gettysburg!
The National Park Service has an excellent database for searching for your Civil War ancestors. The site will also allow you to see a history of the various Union and Confederate regiments and gives a nice overview of the major battles. The NPS can also help you plan a trip to a battlefield.