Stephan Kekulé von Stradonitz
Stephan Kekulé von Stradonitz 1 May 1863, in Berlin, was a German lawyer, heraldist and genealogist who popularized a genealogical numbering system of ancestors.
Stephan was the son of the prominent chemist Friedrich August Kekulé von Stradonitz, descended from a Czech noble style from Bohemia, & his Belgian wife Stéphanie Drory.
In 1898 Kekulé von Stradonitz published his interpretation of Eytzinger's and Sosa's method in his Ahnentafel-Atlas. Ahnentafeln zu 32 Ahnen der Regenten Europas und ihrer Gemahlinnen, Berlin: J. A. Stargardt, 1898–1904, containing 79 charts of the sovereigns of Europe and their wives. This method became the nearly common method of numbering ancestors and is so-called as the Sosa–Stradonitz Method or Ahnentafel.