This is probably the most important single book on early Ohio genealogy, for it references no fewer than 72,000 testators named in the will and estate records for all Ohio counties up to the year 1850. Since will records are the richest source of family relationships, researchers can use this index to access a potential treasure trove of information concerning their families. Each index entry gives the name of the person referenced, the nature of the record (will or estate), the year of the record, the county where the record is filed, and the source of the original record wherein more information may be found. In addition to the index itself, researchers will find a list of abbreviations used in the entries, a glossary of terms common to inheritance records, and a county-by-county breakdown of inheritance record holdings and the individuals responsible for indexing them for the publication.