Donald Lines Jacobus

Donald Lines Jacobus (3 October 1887 – 7 October 1970) was an American genealogist and historian. He was a Fellow of The American Society of Genealogists and the founder of The American Genealogist (TAG). 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.

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

Career Jacobus began working on his genealogical compendium Families of Ancient New Haven in 1912, and it was published in eight volumes between 1922 and 1932.

His other published works include:

Awards Jacobus was the first genealogist to be included in the National Genealogy Hall of Fame by the National Genealogical Society.

Personal life Jacobus never married. He enjoyed tracing the descendants of Spain's King Ferdinand and Queen Isabella.

He died at the Golden Manor Nursing Home in New Haven, Connecticut, on 7 October 1970 following an extended period of illness.