Donald Lines Jacobus

Donald Lines Jacobus, FASG (1887-1970) of New Haven, Connecticut, is widely recognized among genealogists as a prominent figure in American genealogy.

In his publications and teachings, Jacobus underscored the significance of employing a scientific approach to utilizing primary sources in genealogical research. This shifted the focus away from reliance on oral traditions and unquestioned acceptance of longstanding pedigrees as factual solely based on their age. Jacobus established foundational principles for proper documentation and citation that are now considered essential for all genealogists. While Jacobus expressed support for the concept of eugenics, he noted its limitations in accurately tracing bloodlines. He also highlighted the lack of experience among proponents of the field in genealogical research and methodology.

He founded the New Haven Genealogical Magazine in 1922, which later evolved into The American Genealogist (TAG) a decade later. Jacobus held the positions of editor and publisher of the periodical for 43 years, until 1966.

Early life and education
Jacobus was born in New Haven, Connecticut, the only child of John Ira Jacobus (1855-1912), a banker, and Ida Wilmot Lines (1855-1952), daughter of Henry Lines. The Jacobus family's lineage can be traced back to Dutch origins, recorded in Albany, New York, in 1683.

Jacobus received his education at Yale University, earning a Bachelor of Arts degree in 1908, followed by a Master of Arts degree in 1911.

Career
In his youth, Jacobus developed a keen interest in family histories and relationships, often visiting the offices of the New Haven's Town Clerk. At the age of sixteen, he began writing genealogical articles that were published in a Connecticut magazine. After completing his education at Yale University, Jacobus opted not to pursue a career in teaching. Instead, he turned to genealogy. While working as secretary of the New Haven Building and Loan Association from 1912 to 1917 and serving in the U.S. Army between 1917 and 1919, Jacobus continued to compile material on ancient New Haven families in his spare time. For the remainder of his life, he dedicated himself to genealogical research and publication.

Writings
Jacobus was a highly productive writer. In addition to his numerous magazine articles, he authored over a dozen published works, including:


 * Genealogy as Pastime and Profession, published in 1930.
 * History and Genealogy of the Families of Old Fairfield, a three-volume work sponsored by the local Daughters of the American Revolution chapter in Fairfield, Connecticut, from 1930 to 1932.
 * Families of ancient New Haven
 * Hale, House, And Related Families, Mainly of the Connecticut River Valley
 * The Hazen Family in America: A Genealogy
 * A History of the Seymour Family: Descendants of Richard Seymour of Hartford, Connecticut, for Six Generations; With Extensive Amplification of the Lines Deriving from His Son John Seymour of Hartford
 * The American genealogist.

Awards
In acknowledgment of his significant contributions to genealogy, Jacobus became the inaugural individual inducted into the National Genealogy Hall of Fame. His nomination for this honor was put forward by the American Society of Genealogists, the Genealogical Society of Utah, and the DuPage County (IL) Genealogical Society.

In 1972, the American Society of Genealogists established The Donald Lines Jacobus Award to encourage genealogical writing characterized by sound scholarship. Jacobus advocated for the application of the scientific method to genealogical research, emphasizing the importance of primary source documentation. Prior to his influence, many pedigrees relied heavily on unverified oral family histories. His innovative research approach became feasible with the indexing and transcription of early church records and grave stones by heraldic societies, the Church of LDS, and government agencies.

Jacobus was among the earliest Fellows of the American Society of Genealogists, an Honor Society comprising fifty members selected based on the significance of their contributions to genealogy. Following his passing, his colleague Milton Rubincam described Jacobus as "the man who more than any other single individual elevated genealogy to the high degree of scholarship it now occupies."

Personal life
Jacobus remained unmarried and dedicated himself to caring for his widowed mother throughout her lifetime. He enjoyed the hobby of tracing the descendants of Spain's King Ferdinand and Queen Isabella, affectionately referring to them as "Ferdie and Izzie." This demonstrates that while Jacobus took genealogy seriously, he also found enjoyment in its playful and imaginative aspects.

Jacobus passed away at the Golden Manor Nursing Home in New Haven, Connecticut, following an extended period of illness.