"Michaël Eytzinger (Freiherr Michael von Aitzing, Aitzinger, Eyzinger, or Eitzing) (born ca. 1530 in Obereitzing - died 1598 in Bonn), was an Austrian nobleman, diplomat, historian, and publicist, who wrote and published several works, including a renowned volume that states the principles of a genealogical numbering system, called an Ahnentafel, that is still in use today.
Eytzinger first published the Ahnentafel in 1590 in his Thesaurus principum hac aetate in Europa viventium (Cologne), in which he described and illustrated his new functional theory of numeration of ancestors by providing genealogies of thirty-four sovereign houses of Europe. " - (en.wikipedia.org 28.07.2021)
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