This database from the Office of the Illinois Secretary of State, contains information relative to more than 285,000 Illinois soldiers who served the Union during the Civil War. The information comes from the records of the State Adjutant General.
You can search by name or by unit. Once you do a search and get a hit list, click on the individual's name to see much more information.
Check it out at:
Illinois Civil War Muster and Descriptive Rolls Database:
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