9th Regiment, Illinois Infantry (3 months, 1861)
The 9th Regiment, Illinois Infantry (3 months, 1861) was organized at Springfield, Illinois, and mustered in for three months' service April 26, 1861. It was mustered out July 26, 1861. 
For more information on the history of this unit, see:
- The Wikipedia article, 9th Illinois Volunteer Infantry Regiment (3 Months), (accessed 13 June 2012).
- The Civil War Archive section, 9th Regiment Infantry (3 months), (accessed 14 June 2012).
Companies in this Regiment with County of Origin
Men often enlisted in a company recruited in the counties where they lived though not always. After many battles, companies might be combined because so many men were killed or wounded. However if you are unsure which company your ancestor was in, try the company recruited in his county first.
The following counties of origin are taken from the Adjutant General's Report, found on the Illinois Civil War Rosters web site. Roster pages are from the same report found on the Internet Archives web site. The rosters show the men who served in each regiment, their residences, dates of enlistment and mustering out, and other remarks.
- Beginning United States Civil War Research gives steps for finding information about a Civil War soldier. It covers the major records that should be used. Additional records are described in ‘Illinois in the Civil War’ and ‘United States Civil War, 1861 to 1865’ (see below).
- National Park Service, The Civil War Soldiers and Sailors System, is searchable by soldier's name and state. It contains basic facts about soldiers on both sides of the Civil War, a list of regiments, descriptions of significant battles, sources of the information, and suggestions for where to find additional information.
- Illinois in the Civil War describes many Confederate and Union sources, specifically for Illinois, and how to find them.. These include compiled service records, pension records, rosters, cemetery records, Internet databases, published books, etc.
- United States Civil War, 1861 to 1865 describes and explains United States and Confederate States records, rather than state records, and how to find them. These include veterans’ censuses, compiled service records, pension records, rosters, cemetery records, Internet databases, published books, etc.
- National Park Service, The Civil War Soldiers and Sailors System (accessed 4 January 2011).