Genealogy Connect

Who was Donald Lines Jacobus, and why should you care?

By Joe Garonzik

The Connecticut genealogist, Donald Lines Jacobus (pronounced ja cob’ us), was the founder of the modern school of scientific genealogy and the greatest American genealogist of the 20th century. Jacobus and his protégés taught us how to research and write family histories, how to solve genealogical problems, what sources should be used, how to interpret them, and why we must abandon unsupported findings which, in many instances, were built upon flights of imagination as much as on facts.

We could rattle on and on about Jacobus’ achievements [e.g. in 1922, he founded the esteemed periodical, “The American Genealogist,” but we are more concerned to explain why this sage’s teachings and writings are of importance to 21st-century sleuths. Jacobus’ book publications date from 1922, and each one still stands as a model of genealogical scholarship. For example, Families of Ancient New Haven Donald Lines Jacobus is the definitive statement on the ancestry and relationships of 35,000 residents of 18th-century New Haven, Connecticut, and it is the only publication that succeeds in treating every family of an entire New England region. Jacobus left us scores of genealogy articles that appeared in the “National Genealogical Society Quarterly,” “The New England Historical and Genealogical Register,” and his beloved. In 1968, the Genealogical Publishing Company assembled a number of those highly respected essays and published them as Genealogy as a Pastime and Profession.

Genealogy as a Pastime and Profession encapsulates Jacobus’ thinking. It describes the principles of genealogical research, the evaluation of evidence, and the relationship of genealogy to eugenics and the law; it discusses early nomenclature, royal ancestry, the use of source material, and the methods of compiling a family history. Jacobus was a wonderful writer, and he brought all of his wit and erudition to bear in this timeless volume. Beginners and experienced family historians will especially love the case study chapter in which the author the sets out to solve the mysterious ancestries of Ebenezer Couch, Nathaniel Brewster, and John Gill. Whether you do your genealogy over the Internet, by cranking the microfilm reader, or by pouring over old documents, you’ll find that Genealogy as a Pastime and Profession is as useful today as when it was first published 35 years ago and that Jacobus’ advice, by and large, is as reliable as a wise old grandfather’s.

Genealogy as a Pastime and Profession is one of 32 titles in the Genealogy Connect’s Getting Started collection. With a unique collection of research guides called “Genealogy at a Glance,” this group of eBooks lays a rock-solid foundation on which to build your family history. If you’re a beginner to genealogy, start with the simplest book, William Dollarhide’s Managing a Genealogical Project.

Share the knowledge. Share the history. October is National Family History Month! The deeper historic connections in Genealogy Connect is what makes it complimentary to any library’s genealogy resources. 
[alert-info]Joe Garonzik

About the Author

Joe Garonzik, Ph.D., MBA, is the Marketing Director for He has worked at the company for 34 years. His work involves book promotion, content acquisition, and new product development. Joe has represented (and its affiliates Genealogical Publishing Company and Clearfield Company) at genealogy conferences and trade shows over the course of his career. He is married with two grown children, and is of Eastern European descent.



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