99th Illinois Infantry Regiment
| 99th Regiment Illinois Volunteer Infantry | |
|---|---|
Former Illinoisan state flag  | |
| Active | August 23, 1862 – August 9, 1865 | 
| Country | United States | 
| Allegiance | |
| Branch | Union Army | 
| Type | Infantry | 
| Size | Regiment | 
| Engagements | |
| Illinois U.S. Volunteer Infantry Regiments 1861-1865 | ||||
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The 99th Regiment Illinois Volunteer Infantry was an infantry regiment that served in the Union Army during the American Civil War.