The collection description at FamilySearch:
Collection of probate records, which includes will, indexes, and other documents created to track the distribution of estates of deceased individuals who lived in Illinois. Probates were generally recorded in the county of residence. This collection covers probate records created by Illinois courts, 1819-1970, but the content and time period of the records will vary by county. A few additional county court records are also present. Additional records may be added to this collection. Check the wiki or browse the collection to determine current coverage.Learn more about Illinois Probate Books in this article at the FamilySearch Research Wiki.
© 2011, copyright Illinois State Genealogical Society