Originally published in 1993, we have split the original work into two parts and added a supplement containing the 1775 census and two hundreds (subdivisions) of the 1776 census (which were inadvertently omitted from the initial publication) and corrections. This represents a collection of data covering the period: 1773 (when the county was formed) through 1790. Volumes 1 and 2 have been extracted from the following: tax lists of 1774, 1776 (missing two Hundreds now contained in the supplement), 1778, 1783, censuses of 1776 and 1790, Dr. Archer's ledgers, orphans' court proceedings, family Bibles, estate administrations, registers of St. John's and St. George's, Quaker monthly meetings of Deer Creek and Little Falls, wills, court minutes, commercial licenses, survey certificates, land records index, marriage licenses, gleanings from various publications such as the Bulletin of the Historical Society of Harford County and other periodicals and histories, list of Non-Associators and Non-Enrollers in 1775, tombstone inscriptions, and other data drawn from the author's research and collections. This series contains over 30, 000 entries.