The original records on file in Isle of Wight County and abstracted in this work are: Wills and Administrations Book A (1641-1650); Will and Deed Books 1 and 2 (1658-1659, 1666-1719); Will Books 3-11 (1726-1800); Deed Book I (1691-1695); Administrations and Probates (1666-1701); and The Great Book (1719-1729). In addition to the names of the testators and legatees, the entries provide the names of executors, securities, and witnesses and frequently include assignments of property.

An index of wills recorded in local courts of Virginia, 1632-1800, and of administrations on estates shown by inventories of the estates of intestates recorded in will (and other) books of local courts, 1632-1800.

The major part of this work is an alphabetically arranged and cross-indexed list of some 20,000 Maryland families with references to the sources and locations of the records in which they appear. In addition, there is a research record guide arranged by county and type of record, and it identifies all genealogical manuscripts, books, and articles known to exist up to 1940, when this book was first published. Included are church and county courthouse records, deeds, marriages, rent rolls, wills, land records, tombstone inscriptions, censuses, directories, and other data sources.